video_core: Bringup some basic functionality (#145)

* video_core: Remove hack in rasterizer

* The hack was to skip the first draw as the display buffer had not been created yet and the texture cache couldn't create one itself. With this patch it now can, using the color buffer parameters from registers

* shader_recompiler: Implement attribute loads/stores

* video_core: Add basic vertex, index buffer handling and pipeline caching

* externals: Make xxhash lowercase

externals/CMakeLists.txt

@@ -74,8 +74,8 @@ add_subdirectory(magic_enum EXCLUDE_FROM_ALL)
 add_subdirectory(toml11 EXCLUDE_FROM_ALL)
 
 # xxHash
-add_library(xxhash INTERFACE)
-target_include_directories(xxhash INTERFACE xxhash)
+add_library(xxhash xxhash/xxhash.h xxhash/xxhash.c)
+target_include_directories(xxhash PUBLIC xxhash)
 
 # Zydis
 option(ZYDIS_BUILD_TOOLS "" OFF)
@@ -92,4 +92,4 @@ endif()
 add_subdirectory(sirit EXCLUDE_FROM_ALL)
 if (WIN32)
     target_compile_options(sirit PUBLIC "-Wno-error=unused-command-line-argument")
-endif()
+endif()