Fix reg_onhold logic in the last commit, output protocol when reporting onhold status changes.
Fix reg_onhold logic in the last commit, output protocol when
reporting onhold status changes.

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