Fix more memory leaks

Fix more memory leaks

This patch adds to what was fixed in r366880.  Specifically, it addresses the
following:

* chan_sip:   dispose of an allocated frame in off nominal code paths in
              sip_rtp_read
* func_odbc:  when disposing of an allocated resultset, ensure that any rows
              that were appended to that resultset are also disposed of
* cli:        free the created return string buffer in another off nominal code
              path
* chan_dahdi: free a frame that was allocated by the dsp layer if we choose
              not to process that frame

(issue ASTERISK-19665)
Reported by: Matt Jordan

Review: https://reviewboard.asterisk.org/r/1922/
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Merged revisions 366944 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 366948 from http://svn.asterisk.org/svn/asterisk/branches/10

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@366955 65c4cc65-6c06-0410-ace0-fbb531ad65f3