GPU: Allow the usage of RGBA16_FLOAT in the texture copy engine.

src/video_core/gpu.cpp

@@ -28,6 +28,8 @@ u32 RenderTargetBytesPerPixel(RenderTargetFormat format) {
     switch (format) {
     case RenderTargetFormat::RGBA32_FLOAT:
         return 16;
+    case RenderTargetFormat::RGBA16_FLOAT:
+        return 8;
     case RenderTargetFormat::RGBA8_UNORM:
     case RenderTargetFormat::RGB10_A2_UNORM:
         return 4;