Add empty interface implementation to metal

Author: baldurk

renderdoc/driver/metal/metal_device.h

@@ -47,6 +47,18 @@ class MetalCapturer : public IFrameCapturer
   void StartFrameCapture(DeviceOwnedWindow devWnd);
   bool EndFrameCapture(DeviceOwnedWindow devWnd);
   bool DiscardFrameCapture(DeviceOwnedWindow devWnd);
+
+  uint32_t SetObjectAnnotation(void *object, const char *key, RENDERDOC_AnnotationType valueType,
+                               uint32_t valueVectorWidth, const RENDERDOC_AnnotationValue *value)
+  {
+    return 2;
+  }
+  uint32_t SetCommandAnnotation(void *queueOrCommandBuffer, const char *key,
+                                RENDERDOC_AnnotationType valueType, uint32_t valueVectorWidth,
+                                const RENDERDOC_AnnotationValue *value)
+  {
+    return 2;
+  }
   // IFrameCapturer interface
 
 private: