drm/amdgpu: support athub cg setting for dimgrey_cavefish

Same as navy_flounder, the athub ip of dimgrey_cavefish is v2.1.
Signed-off-by: Tao Zhou <tao.zhou1@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/athub_v2_1.c

@@ -74,6 +74,7 @@ int athub_v2_1_set_clockgating(struct amdgpu_device *adev,
 	switch (adev->asic_type) {
 	case CHIP_SIENNA_CICHLID:
 	case CHIP_NAVY_FLOUNDER:
+	case CHIP_DIMGREY_CAVEFISH:
 		athub_v2_1_update_medium_grain_clock_gating(adev,
 				state == AMD_CG_STATE_GATE ? true : false);
 		athub_v2_1_update_medium_grain_light_sleep(adev,