drm/amd/pp: Get and save Rv smu version

The smu firmware is loaded by the sbios on APUs, so query it
from the smu and save the smu fw version info that is reported
to userspace.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>