drm/amdgpu: add golden setting for gc_11_5_0

Initialize golden setting for gc_11_5_0.

v2: squash in latest golden updates (Alex)
v3: squash in checkpatch fix (Alex)

Signed-off-by: Aaron Liu <aaron.liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>