drm/amdgpu: Add flag to enable indirect RLCG access for gfx v9.4.3

The "rlcg_reg_access_supported" flag is missing. Add it back in.

Signed-off-by: Victor Lu <victorchengchi.lu@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>