drm/amd/pm: Add common throttler translation func

Defines smu_cmn_get_indep_throttler_status which performs ASIC
independent translation given a corresponding lookup table.

Signed-off-by: Graham Sider <Graham.Sider@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>