[sr-dev] [kamailio/kamailio] rtpengine: query rtt per call leg (#2576)

#### Type Of Change - [x] New feature (non-breaking change which adds new functionality)

#### Checklist: - [x] Tested changes locally

#### Description This modification is to provide access to the new exposed metrics.

RTPengine is now keeping track of RTT per call leg https://github.com/sipwise/rtpengine/pull/1116

You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/2576

-- Commit Summary --

* rtpengine: query rtt per call leg

-- File Changes --

M src/modules/rtpengine/doc/rtpengine_admin.xml (185) M src/modules/rtpengine/rtpengine.c (17)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/2576.patch https://github.com/kamailio/kamailio/pull/2576.diff