Quote the arguments to grep so that sh on various platforms doesn't choke

on the special characters (like ^).

(closes issue #13417)
Reported by: dougm
Patches:
      13417.make_buildopts_h.patch uploaded by seanbright (license 71)
Tested by: dougm


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@141682 65c4cc65-6c06-0410-ace0-fbb531ad65f3