configure instead of the icky loop I was doing before).

(closes issue #13842)
Reported by: snuffy
Patches:
      bug13842_20081106.diff uploaded by snuffy (license 35)
      13842.diff uploaded by seanbright (license 71)
Tested by: snuffy


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@157600 65c4cc65-6c06-0410-ace0-fbb531ad65f3