libpjsip: security bump to 2.7.2
Fixes the following vulnerabilities:
- CVE-2018-1000098: Crash when parsing SDP with an invalid media format
description
- CVE-2018-1000099: Crash when receiving SDP with invalid fmtp attribute
[Peter: add CVE info]
Signed-off-by: Adam Duskett <aduskett@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>