drm/amdgpu: add vce bypass mode for tonga.

fix issue that encode test failed on the second time when
vce dpm enabled on tonga.

Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/vce_v3_0.c

@@ -715,7 +715,8 @@ static int vce_v3_0_set_clockgating_state(void *handle,
 	bool enable = (state == AMD_CG_STATE_GATE) ? true : false;
 	int i;
 
-	if (adev->asic_type == CHIP_POLARIS10)
+	if ((adev->asic_type == CHIP_POLARIS10) ||
+	    (adev->asic_type == CHIP_TONGA))
 		vce_v3_0_set_bypass_mode(adev, enable);
 
 	if (!(adev->cg_flags & AMD_CG_SUPPORT_VCE_MGCG))