Remove netdb.h include; already included from conf.h

PR:
Obtained from:
Submitted by:
Reviewed by:	Dirk-Willem van Gulik, Roy T. Fielding


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@79705 13f79535-47bb-0310-9956-ffa450edef68