Logger: Fix MALLOC_DEBUG build error.

Revision 432834 introduced a build error when MALLOC_DEBUG
is used.  Switch callid threadstorage to simple
AST_THREADSTORAGE since we no longer need custom cleanup.

Reported by: Corey Farrell


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@432851 65c4cc65-6c06-0410-ace0-fbb531ad65f3