Extend on_session_end to be substructure that contains both function pointer as well as size of its argument.
Extend on_session_end to be substructure that contains both
function pointer as well as size of its argument.

dsanders11/rtpproxy,sippy/rtpproxy,synety-jdebp/rtpproxy,jevonearth/rtpproxy,jevonearth/rtpproxy,synety-jdebp/rtpproxy,dsanders11/rtpproxy,dsanders11/rtpproxy,synety-jdebp/rtpproxy,jevonearth/rtpproxy,sippy/rtpproxy,jevonearth/rtpproxy,synety-jdebp/rtpproxy,sippy/rtpproxy