drm/amd/powerplay: check for invalid profile mode before switching

Need to check for invalid profile mode settings before determining
to switch to that.

Signed-off-by: Evan Quan <evan.quan@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>