drm/amdgpu: correct NBIO v7.11 programing

Use v7.7 before, switch to v7.11 now.
Fix incorrect programing.

Signed-off-by: Lang Yu <Lang.Yu@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Yifan Zhang <yifan1.zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>