MFH: r500705 r500724

• Add to pjsip a customized config_site.h file with values suggested by the asterisk project. This allows WebRTC to work correctly in asterisk out of the box [1]
• Also import some patches to pjsip from the asterisk project. These patches have already been integrated in upstream pjsip development sources [2]

Reported by: zhenya1993lzn@yandex.ru [1]
Obtained from: https://github.com/asterisk/asterisk/tree/16.3/third-party/pjproject/patches [2]

Bump PORTREVISION on asterisk ports after r500705 changes to pjsip.
Crashes have been reported, which are fixed by reinstallation.

Reported by: Christoph Moench-Tegeder <cmt@burggraben.net>

Approved by: ports-secteam (joneum, miwi)