drm/amd/powerplay: drop unnecessary message support check(v2)

Take back patch:drop unnecessary message support check
Because the gpu reset fail problem on renoir can be fixed by:
drm/amd/powerplay: skip invalid msg when smu set mp1 state
It needs to remove SWSMU_CODE_LAYER_L1 in smu_cmn.h to guard a clear
code layer.

Signed-off-by: changfeng <Changfeng.Zhu@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>