Cleanup a bit more by getting rid of useless version defines. Also make...

Cleanup a bit more by getting rid of useless version defines. Also make library detection use passed CFLAGS.

(closes issue #17309)
 Reported by: stuarth


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@262102 65c4cc65-6c06-0410-ace0-fbb531ad65f3