drm/amd/pp: Delete is_smc_ram_running function on RV

1. There is a race condition when another ip also use same register pairs
2. check once at boot up by GetDriverIfVersion message is sufficient
   to check SMU health. so delete is_smc_ram_running check.

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>