Externals: Add glslang from Vulkan SDK v1.0.21.1

Externals/glslang/SPIRV/CMakeLists.txt

@@ -0,0 +1,29 @@
+set(SOURCES
+    GlslangToSpv.cpp
+    InReadableOrder.cpp
+    Logger.cpp
+    SpvBuilder.cpp
+    SPVRemapper.cpp
+    doc.cpp
+    disassemble.cpp)
+
+set(HEADERS
+    spirv.hpp
+    GLSL.std.450.h
+    GlslangToSpv.h
+    Logger.h
+    SpvBuilder.h
+    SPVRemapper.h
+    spvIR.h
+    doc.h
+    disassemble.h)
+
+add_library(SPIRV STATIC ${SOURCES} ${HEADERS})
+set_property(TARGET SPIRV PROPERTY FOLDER glslang)
+
+if(WIN32)
+    source_group("Source" FILES ${SOURCES} ${HEADERS})
+endif(WIN32)
+
+install(TARGETS SPIRV
+        ARCHIVE DESTINATION lib)