Janitor project: convert free to ast_free

(closes issue #13082)
Reported by: eliel
Patches:
      app_rpt.c.patch uploaded by eliel (license 64)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@131529 65c4cc65-6c06-0410-ace0-fbb531ad65f3