Merged revisions 317865 via svnmerge from

Merged revisions 317865 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r317865 | russell | 2011-05-06 14:46:49 -0500 (Fri, 06 May 2011) | 11 lines

  chan_sip: fix a deadlock in check_rtp_timeout.

  Don't block doing silly deadlock avoidance.  Just return and try again later.
  The funciton gets called often enough that it's fine.  Also, this change was
  already made in trunk.

  (closes issue #18791)
  Reported by: irroot
  Patches:
        chan_sip.rtptimeout.patch uploaded by irroot (license 52)
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@317866 65c4cc65-6c06-0410-ace0-fbb531ad65f3