Calling weston_output_mode_switch() with WESTON_MODE_SWITCH_RESTORE_NATIVE
will result in the mode being set "back" to the passed in mode - so the
passed mode should be the native mode.
Additionally, weston_output_mode_switch() should be called when
output->original_mode is non-NULL (which indicates we had a temporary
mode set). The comparison to current_mode results in a lot of
log chatter.
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
