Fix a comparison with ENOENT which was accidently broken during

the canonical error cleanup.

We wish to avoid reporting the boring error where we try to unlink
a socket which doesn't already exist.  We only want to report
interesting stuff.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@87298 13f79535-47bb-0310-9956-ffa450edef68