drm/amdgpu: Remove unused nbif_v6_3_1_sriov_funcs
The nbif_v6_3_1_sriov_funcs instance of amdgpu_nbio_funcs was added in
commit
894c6d3522d1 ("drm/amdgpu: Add nbif v6_3_1 ip block support")
but has remained unused.
Alex has confirmed it wasn't needed.
Remove it, together with the four unused stub functions:
nbif_v6_3_1_sriov_ih_doorbell_range
nbif_v6_3_1_sriov_gc_doorbell_init
nbif_v6_3_1_sriov_vcn_doorbell_range
nbif_v6_3_1_sriov_sdma_doorbell_range
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>