Avoid allocating memory for a thread that don't need it. Also, this memory was...

Avoid allocating memory for a thread that don't need it. Also, this memory was not being freed until the
main thread ends. (That is never).

(closes issue #14040)
Reported by: eliel
Patches:
      func_odbc.c.patch uploaded by eliel (license 64)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@161947 65c4cc65-6c06-0410-ace0-fbb531ad65f3