drm/amdgpu/vcn3.0: remove extra asic type check

vcn ip block is already selected based on ASIC type during set_ip_blocks.

Signed-off-by: James Zhu <James.Zhu@amd.com>
Reviewed-by: Leo Liu <leo.liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>