Add SPIR-V tools dependency to BUILD.gn files

Since we track the SPV_ENV_... version with VkConfig.hpp, any other
directory that includes VkConfig has to have a dependency on SPIR-V
Tools.

Bug: b/172837769
Change-Id: I7962ee278c3240c9461acaedcd9cbbca0c08c0d6
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/50208
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Tested-by: Sean Risser <srisser@google.com>

src/Device/BUILD.gn

diff --git a/src/Device/BUILD.gn b/src/Device/BUILD.gn
index 0823585..d444f90 100644
--- a/src/Device/BUILD.gn
+++ b/src/Device/BUILD.gn
@@ -73,6 +73,7 @@
   ]
 
   deps = [
+    "${swiftshader_spirv_tools_dir}:SPIRV-Tools",
     "../../third_party/marl:Marl_headers",
     "../Pipeline:Pipeline_headers",
     "../System:System_headers",

src/WSI/BUILD.gn

diff --git a/src/WSI/BUILD.gn b/src/WSI/BUILD.gn
index fa37f94..2116b63 100644
--- a/src/WSI/BUILD.gn
+++ b/src/WSI/BUILD.gn
@@ -68,6 +68,7 @@
   ]
 
   deps = [
+    "${swiftshader_spirv_tools_dir}:SPIRV-Tools",
     "../../third_party/marl:Marl_headers",
     "../System",
     "../Vulkan:swiftshader_libvulkan_headers",