Temporarily disable warnings-as-errors

Updating SPIRV-Headers adds new enum entries that are not handled by switch cases, which causes a warning / error.

This will be put back once SPIRV-Tools is also updated.

Change-Id: If803398edb9d44753bf3b277dadd060268ea3755
diff --git a/CMakeLists.txt b/CMakeLists.txt
index cc702b2..c9c0902 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -93,12 +93,14 @@
 option(ASAN "Build with address sanitizer" 0)
 option(TSAN "Build with thread sanitizer" 0)
 option(UBSAN "Build with undefined behavior sanitizer" 0)
-option(WARNINGS_AS_ERRORS "Treat all warnings as errors" 1)
+option(WARNINGS_AS_ERRORS "Treat all warnings as errors" 0)
 option(DCHECK_ALWAYS_ON "Check validation macros even in release builds" 0)
 option(REACTOR_EMIT_DEBUG_INFO "Emit debug info for JIT functions" 0)
 option(REACTOR_EMIT_PRINT_LOCATION "Emit printing of location info for JIT functions" 0)
 option(REACTOR_VERIFY_LLVM_IR "Check reactor-generated LLVM IR is valid even in release builds" 0)
 
+set(SPIRV_WERROR OFF CACHE BOOL "TEMPORARY WHILE UPDATING SPIRV-Headers SPIRV-Tools")
+
 if(ARCH STREQUAL "arm")
     set(DEFAULT_REACTOR_BACKEND "Subzero")
 else()