drm/amd/pm: fix enabled features retrieving on Renoir and Cyan Skillfish

For Cyan Skillfish and Renoir, there is no interface provided by PMFW
to retrieve the enabled features. So, we assume all features are enabled.

Fixes: 7ade3ca9 ("drm/amd/pm: correct the usage for 'supported' member of smu_feature structure")

Signed-off-by: Evan Quan <evan.quan@amd.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>