Merged revisions 325740 via svnmerge from

Merged revisions 325740 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r325740 | kmoore | 2011-06-29 16:49:21 -0500 (Wed, 29 Jun 2011) | 7 lines

  chan_sip: cleanup from the introduction of ast_str

  Remove the length field from sip_req and sip_pkt in chan_sip since they are
  redundant (ast_str holds its own length) and refactor the necessary functions.

  Review: https://reviewboard.asterisk.org/r/1281/
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@325741 65c4cc65-6c06-0410-ace0-fbb531ad65f3