cmake: fix linking of stubbed libraries

SPIRV/CMakeLists.txt

@@ -111,11 +111,11 @@ if(WIN32 AND BUILD_SHARED_LIBS)
 endif()
 
 if(ENABLE_OPT)
-    target_link_libraries(SPIRV PRIVATE glslang PUBLIC SPIRV-Tools-opt)
+    target_link_libraries(SPIRV INTERFACE glslang PUBLIC SPIRV-Tools-opt)
     target_include_directories(SPIRV PUBLIC
         $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/../External>)
 else()
-    target_link_libraries(SPIRV PRIVATE glslang)
+    target_link_libraries(SPIRV INTERFACE glslang)
 endif()
 
 if(WIN32)

glslang/CMakeLists.txt

@@ -136,7 +136,7 @@ endif()
 add_library(MachineIndependent STATIC stub.cpp)
 set_property(TARGET MachineIndependent PROPERTY POSITION_INDEPENDENT_CODE ON)
 set_property(TARGET MachineIndependent PROPERTY FOLDER glslang)
-target_link_libraries(MachineIndependent PRIVATE glslang)
+target_link_libraries(MachineIndependent INTERFACE glslang)
 
 if (NOT MSVC)
     # -Wunused-but-set-variable is triggered in code generated by bison that we do not control. Turn this warning off, but only for the generated.