hidecalleridname parameter in chan_dahdi.conf

hidecalleridname parameter in chan_dahdi.conf

Issue #7321 implements a new chan_dahdi configuration option.  However, a
change mentioned in the issue was never implemented.  This is the change
that will allow the feature to work.

I added a note to chan_dahdi.conf.sample about the feature.

(closes issue #17143)
Reported by: djensen99
Patches:
      diff.txt uploaded by djensen99 (license NA) (One line change)
Tested by: djensen99

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@259270 65c4cc65-6c06-0410-ace0-fbb531ad65f3