Fix a mild race condition in unblock_alarms() involving a SIGALRM showing

up after a SIGTERM.

PR:		1211
Reviewed by:	Marc Slemko, Martin Kraemer


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@79498 13f79535-47bb-0310-9956-ffa450edef68