Avoid rare but potential problems if errno is reset while syncing scoreboard

or if timeout intercepts after lingering_close.

Reviewed by: Marc Slemko, Jim Jagielski, Chuck Murcko, Randy Terbush


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@77632 13f79535-47bb-0310-9956-ffa450edef68