Merged revisions 316224 via svnmerge from

Merged revisions 316224 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r316224 | rmudgett | 2011-05-03 14:18:30 -0500 (Tue, 03 May 2011) | 16 lines

  The dahdi_hangup() call does not clean up the channel fully.

  After dahdi_hangup() has supposedly hungup an ISDN channel there is still
  traffic on the S0-bus because the channel was not cleaned up fully.

  Shuffled the hangup code to include some missing cleanup.  Also fixed some
  code formatting in the area.  I think the primary missing clean up code
  was the call to tone_zone_play_tone() to turn off any active tones on the
  channel.

  (closes issue #19188)
  Reported by: jg1234
  Patches:
        issue19188_v1.8.patch uploaded by rmudgett (license 664)
  Tested by: jg1234
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@316240 65c4cc65-6c06-0410-ace0-fbb531ad65f3