Add a comment that linux22 (-DLINUX22) is not solely for Linux-2.2.x

Submitted by:	jean-frederic clere <jfrederic.clere@fujitsu-siemens.com>


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@88385 13f79535-47bb-0310-9956-ffa450edef68