drm/amd/pm: Initialize power limit for SMU v13.0.6

PMFW will initialize the power limit values even if PPT throttler
feature is disabled. Fetch the limit value from FW.

Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Asad Kamal <asad.kamal@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>