drm/radeon/kms: fix radeon mid power profile reporting

Fix incorrectly reporting 'default' power profile, when it is set to 'mid'.

Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>
Reviewed-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>