CMake: Make the use of endif() / endif(EXPR) consistent

Only use the condition in the `endif()` if:
• The opening `if()` is more than 20 lines away.
• The `endif()` doesn't belong to an `elif()`.

Also remove redundant sequences of `endif(SWIFTSHADER_BUILD_TESTS)` `if(SWIFTSHADER_BUILD_TESTS)`

Bug: None. Style bikeshedding
Change-Id: I967948a2afdedbd503add5addffc666c698eb885
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/40468
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Tested-by: Ben Clayton <bclayton@google.com>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index cd93e62..32a13c6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -70,7 +70,7 @@
     message(STATUS "Using ccache")
     set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ccache)
     set_property(GLOBAL PROPERTY RULE_LAUNCH_LINK ccache)
-endif(CCACHE_FOUND)
+endif()
 
 ###########################################################
 # Host libraries
@@ -1432,7 +1432,7 @@
     list(APPEND LLVM_LIST
         ${LLVM_DIR}/lib/Demangle/ItaniumDemangle.cpp
     )
-endif(REACTOR_EMIT_DEBUG_INFO)
+endif()
 
 set(LLVM_INCLUDE_DIR "")
 
@@ -1506,7 +1506,7 @@
 # Add required libraries for LLVM
 if(LINUX)
     target_link_libraries(llvm dl)
-endif(LINUX)
+endif()
 
 ###########################################################
 # Subzero
@@ -1639,7 +1639,7 @@
     if(WIN32)
         target_compile_definitions(ReactorSubzero PRIVATE SUBZERO_USE_MICROSOFT_ABI)
     endif()
-endif()
+endif(${REACTOR_BACKEND} STREQUAL "Subzero")
 
 ###########################################################
 # Include Directories
@@ -1834,13 +1834,13 @@
     )
     list(APPEND VULKAN_LIST ${VULKAN_DEBUG_LIST})
     list(APPEND SWIFTSHADER_COMPILE_OPTIONS "-DENABLE_VK_DEBUGGER")
-endif(SWIFTSHADER_ENABLE_VULKAN_DEBUGGER)
+endif()
 
 if(LINUX OR ANDROID)
     list(APPEND VULKAN_LIST
         ${SOURCE_DIR}/System/Linux/MemFd.cpp
 	${SOURCE_DIR}/System/Linux/MemFd.hpp)
-endif(LINUX OR ANDROID)
+endif()
 
 ###########################################################
 # Append OS specific files to lists
@@ -1888,14 +1888,14 @@
             ${SOURCE_DIR}/WSI/libX11.cpp
             ${SOURCE_DIR}/WSI/libX11.hpp
         )
-    endif(X11)
+    endif()
 
     if(XCB)
         list(APPEND VULKAN_LIST
             ${SOURCE_DIR}/WSI/XcbSurfaceKHR.cpp
             ${SOURCE_DIR}/WSI/XcbSurfaceKHR.hpp
         )
-    endif(XCB)
+    endif()
 
 elseif(APPLE)
     list(APPEND SWIFTSHADER_LIST
@@ -2024,7 +2024,7 @@
     if(LINUX)
         if(X11)
             set_property(TARGET libEGL APPEND PROPERTY COMPILE_DEFINITIONS "USE_X11=1")
-        endif(X11)
+        endif()
     endif()
     if (ANDROID)
         set_target_properties(libEGL PROPERTIES SUFFIX "_swiftshader.so")
@@ -2085,17 +2085,17 @@
         COMMAND ${CMAKE_COMMAND} -E make_directory $<TARGET_FILE_DIR:libGLES_CM>/translator
         COMMAND ${CMAKE_COMMAND} -E copy $<TARGET_FILE:libGLES_CM> $<TARGET_FILE_DIR:libGLES_CM>/translator/${LIB_PREFIX}GLES_CM_translator${CMAKE_SHARED_LIBRARY_SUFFIX}
     )
-endif()
+endif(SWIFTSHADER_BUILD_GLES_CM)
 
 if(BUILD_MARL)
     set(MARL_THIRD_PARTY_DIR ${THIRD_PARTY_DIR})
     add_subdirectory(third_party/marl)
-endif(BUILD_MARL)
+endif()
 
 if(SWIFTSHADER_BUILD_CPPDAP)
     set(CPPDAP_THIRD_PARTY_DIR ${THIRD_PARTY_DIR})
     add_subdirectory(${CPPDAP_DIR})
-endif(SWIFTSHADER_BUILD_CPPDAP)
+endif()
 
 if(SWIFTSHADER_BUILD_VULKAN)
     add_library(vk_swiftshader SHARED ${VULKAN_LIST})
@@ -2106,7 +2106,7 @@
         list(APPEND VULKAN_INCLUDE_DIR "${SPIRV-Headers_SOURCE_DIR}/include")
 
         add_subdirectory(third_party/SPIRV-Tools)
-    endif(NOT TARGET SPIRV-Tools)
+    endif()
 
     # Copy the OpenCLDebugInfo100.h header that's generated by SPIRV-Tools
     # out to a separate directory that can be added to the include path.
@@ -2136,11 +2136,11 @@
         if(X11)
             set_property(TARGET vk_swiftshader APPEND
                         PROPERTY COMPILE_DEFINITIONS "VK_USE_PLATFORM_XLIB_KHR")
-        endif(X11)
+        endif()
         if(XCB)
             set_property(TARGET vk_swiftshader APPEND
                         PROPERTY COMPILE_DEFINITIONS "VK_USE_PLATFORM_XCB_KHR")
-        endif(XCB)
+        endif()
     elseif(APPLE)
         set_property(TARGET vk_swiftshader APPEND
                      PROPERTY COMPILE_DEFINITIONS "VK_USE_PLATFORM_MACOS_MVK")
@@ -2151,7 +2151,7 @@
     set(VK_SWIFTSHADER_LIBS ${Reactor} marl ${OS_LIBS} SPIRV-Tools SPIRV-Tools-opt)
     if(SWIFTSHADER_ENABLE_VULKAN_DEBUGGER)
         list(APPEND VK_SWIFTSHADER_LIBS cppdap)
-    endif(SWIFTSHADER_ENABLE_VULKAN_DEBUGGER)
+    endif()
     target_link_libraries(vk_swiftshader ${VK_SWIFTSHADER_LIBS})
 
     add_custom_command(
@@ -2176,7 +2176,7 @@
     configure_file(
         "${VULKAN_DIR}/vk_swiftshader_icd.json.tmpl"
         "${CMAKE_BINARY_DIR}/${CMAKE_SYSTEM_NAME}/vk_swiftshader_icd.json")
-endif()
+endif(SWIFTSHADER_BUILD_VULKAN)
 
 ###########################################################
 # Sample programs
@@ -2218,7 +2218,7 @@
             MACOSX_PACKAGE_LOCATION "Resources"
         )
     endif()
-endif()
+endif(SWIFTSHADER_BUILD_SAMPLES)
 
 
 if(SWIFTSHADER_BUILD_TESTS)
@@ -2244,9 +2244,7 @@
     else()
         target_link_libraries(ReactorUnitTests ${Reactor})
     endif()
-endif()
 
-if(SWIFTSHADER_BUILD_TESTS)
     set(GLES_UNITTESTS_LIST
         ${CMAKE_CURRENT_SOURCE_DIR}/tests/GLESUnitTests/main.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/tests/GLESUnitTests/unittests.cpp
@@ -2272,9 +2270,7 @@
     if(ANDROID)
         target_link_libraries(gles-unittests -landroid)
     endif()
-endif(SWIFTSHADER_BUILD_TESTS)
 
-if(SWIFTSHADER_BUILD_TESTS)
     # Math unit tests
     set(MATH_UNITTESTS_LIST
         ${CMAKE_CURRENT_SOURCE_DIR}/tests/MathUnitTests/main.cpp
@@ -2299,7 +2295,7 @@
     if(NOT WIN32)
         target_link_libraries(math-unittests pthread)
     endif()
-endif()
+endif(SWIFTSHADER_BUILD_TESTS)
 
 if(SWIFTSHADER_BUILD_TESTS AND SWIFTSHADER_BUILD_VULKAN)
     set(VK_UNITTESTS_LIST