merge r1551802 from trunk:

mod_ldap: restrict a recent WIN32 change to only apply when the MS SDK is used.

Submitted by: covener:
Reviewed by: jim, trawick



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1555722 13f79535-47bb-0310-9956-ffa450edef68