K 10
svn:author
V 3
kib
K 8
svn:date
V 27
2017-06-17T11:29:59.820414Z
K 7
svn:log
V 302
Do not leak syslog_mutex on cancellation.

Make syslog(3) resilent to cancellation occuring in supported deferred
mode.  Code must unlock syslog_mutex on cancel, install the cleanup
handler.

Diagnosed and tested by:	eugen
Discussed with:	dchagin
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week

END