drm/amdgpu: add no_user_fence flag to ring funcs

So we can generalize the no user fence supported engine
Signed-off-by: Leo Liu <leo.liu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h

@@ -114,6 +114,7 @@ struct amdgpu_ring_funcs {
 	uint32_t		align_mask;
 	u32			nop;
 	bool			support_64bit_ptrs;
+	bool			no_user_fence;
 	unsigned		vmhub;
 	unsigned		extra_dw;