query_cache: Abstract OpenGL implementation

Abstract the current OpenGL implementation into the VideoCommon
namespace and reimplement it on top of that. Doing this avoids repeating
code and logic in the Vulkan implementation.

src/video_core/CMakeLists.txt

@@ -37,6 +37,7 @@ add_library(video_core STATIC
     memory_manager.h
     morton.cpp
     morton.h
+    query_cache.h
     rasterizer_accelerated.cpp
     rasterizer_accelerated.h
     rasterizer_cache.cpp