drm/amdgpu/vcn: set no_user_fence for VCN v2.5 enc/dec rings

drm/amdgpu/vcn: set no_user_fence for VCN v2.5 enc/dec rings

VCN encoder and decoder rings do not support 64-bit user fence writes,
reject CS submissions with user fences.

Fixes: 28c17d72072b ("drm/amdgpu: add VCN2.5 basic supports")
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Yinjie Yao <yinjie.yao@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit efc9dd5590894109bce9a0bfe1fa5592dd6b20b1)