drm/amd/pm: support ss metrics read for smu11

support reading smartshift apu and dgpu power for smu11 based asic

v2: add new version of SmuMetrics and make calculation more readable (Lijo)
v3: avoid calculations that result in -ve values and skip related checks
v4: use the current power limit on dGPU and exclude smu 11_0_7 (Lijo)
v5: remove redundant code (Lijo)

Signed-off-by: Sathishkumar S <sathishkumar.sundararaju@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>