fix griffin builds

Author: hunterk

griffin/griffin_cpp.cpp

@@ -79,6 +79,7 @@ VIDEO DRIVER
 #include "../deps/SPIRV-Cross/spirv_cross_parsed_ir.cpp"
 #ifdef HAVE_SLANG
 #include "../gfx/drivers_shader/slang_process.cpp"
+#include "../gfx/drivers_shader/slang_cache.cpp"
 #endif
 #endif