res_rtp_asterisk: Ensure that the thread terminating pj stuff is registered.
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Merged revisions 423253 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 423254 from http://svn.asterisk.org/svn/asterisk/branches/12
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Merged revisions 423255 from http://svn.asterisk.org/svn/asterisk/branches/13


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@423256 f38db490-d61c-443f-a65b-d21fe96a405b