Externals: Update glslang to 16.0.0 and allow using system glslang

Source/Core/VideoBackends/D3DCommon/CMakeLists.txt

@@ -12,15 +12,8 @@ PUBLIC
   common
   videocommon
   spirv_cross
-)
-
-target_include_directories(videod3dcommon
-SYSTEM PUBLIC
-  ${CMAKE_SOURCE_DIR}/Externals/glslang/glslang/Public
-SYSTEM PRIVATE
-  ${CMAKE_SOURCE_DIR}/Externals/glslang/StandAlone
-  ${CMAKE_SOURCE_DIR}/Externals/glslang/SPIRV
-  ${CMAKE_SOURCE_DIR}/Externals/glslang
+PRIVATE
+  glslang::glslang
 )
 
 if(MSVC)

Source/Core/VideoBackends/D3DCommon/Shader.cpp

@@ -8,8 +8,8 @@
 #include <string_view>
 
 #include <fmt/format.h>
+#include <glslang/SPIRV/disassemble.h>
 #include <wrl/client.h>
-#include "disassemble.h"
 #include "spirv_hlsl.hpp"
 
 #include "Common/Assert.h"

Source/Core/VideoBackends/Metal/CMakeLists.txt

@@ -35,6 +35,7 @@ PUBLIC
   videocommon
 PRIVATE
   spirv_cross
+  glslang::glslang
   ${FOUNDATION_LIBRARY}
   ${METAL_LIBRARY}
   ${QUARTZCORE_LIBRARY}

Source/Core/VideoBackends/Vulkan/CMakeLists.txt

@@ -44,7 +44,7 @@ PUBLIC
 
 PRIVATE
   # Link against glslang, the other necessary libraries are referenced by the executable.
-  glslang
+  glslang::glslang
   xxhash::xxhash
 )