drm/amd/pm: drop most smu_cmn_get_smc_version in smu

smu_check_fw_version is called in smu hw init, thus smu if version
and version are garenteed to be stored in smu context. No need to
call smu_cmn_get_smc_version again after system boot up.

Signed-off-by: Yifan Zhang <yifan1.zhang@amd.com>
Reviewed-by: Kenneth Feng <kenneth.feng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>