Return g729 and g723.1 frames with the number of samples set properly.

If the wctc4xxp returns more than a single packet, we need to update the number
of samples in the returned frame accordingly.

Acked-by: Shaun Ruffell <sruffell@digium.com>
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Merged revisions 358484 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 358485 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@358486 65c4cc65-6c06-0410-ace0-fbb531ad65f3