drm/amd/powerplay: check for invalid profile_exit setting

profile_exit performance level setting is valid only
when current mode is in profile mode.

Signed-off-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Tao Zhou <tao.zhou1@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>