Remove use of deprecated wfGetIP()

Function has been deprecated since 1.19, when WebRequest::getIP() was added.

Also removed unnecessary require_once lines, one of which would cause a fatal
error since e4bcbe722ebb in core. That commit moved includes/IP.php to
includes/utils/IP.php .

Change-Id: Ic947c0c4a1728707046b172126ad31e4c9cd4edd
Merge "Remove use of deprecated wfGetIP()"