drm/amdgpu: Enable xgmi extended peer links for sriov guest

drm/amdgpu: Enable xgmi extended peer links for sriov guest

The amd-smi tool relies on extended peer link information to report xgmi
link metrics. The necessary xgmi ta command, GET_EXTEND_PEER_LINKS, has
been enabled in the host driver and this change is necessary for the
guest to make use of it. To handle the case where the host driver does
not have the latest xgmi ta, the guest driver checks for guest support
through a pf2vf feature flag before invoking psp.

Signed-off-by: Will Aitken <wiaitken@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>