WinNT MPM: Fix INVALID_SOCKET bogosity

The related code and a lot more was removed from trunk in r730828.

This doesn't address any reported problem symptom.

Submitted by: trawick
Reviewed by: druggeri, rpluem


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@1373349 13f79535-47bb-0310-9956-ffa450edef68