drm/amdgpu: add missing breaks

Saves a few CPU cycles.
Reviewed-by: NChunming zhou <david1.zhou@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -1080,6 +1080,7 @@ int amdgpu_set_clockgating_state(struct amdgpu_device *adev,
 									    state);
 			if (r)
 				return r;
+			break;
 		}
 	}
 	return r;
@@ -1097,6 +1098,7 @@ int amdgpu_set_powergating_state(struct amdgpu_device *adev,
 									    state);
 			if (r)
 				return r;
+			break;
 		}
 	}
 	return r;