Fix a possible kernel panic in ucom(4) that is caused by ttyclose() using data already freed by ucom_close().
Fix a possible kernel panic in ucom(4) that is caused by ttyclose() using data
already freed by ucom_close().

Problem reported and initial patch provided by Marc Winiger <marc@winiger.ch>

ok miod, deraadt

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars