This is a rather hillarious bug:
https://www.libssh.org/security/advisories/CVE-2018-10933.txt
Luckily none of our stuff in HaikuPorts actually uses this.
Thanks @waddlesplash for notifying
Changes to recipe:
- Cleaned up cmake call
- Added ugly hack for `-pie` and `-fstack-protector`, probably a cmake
bug, but since linux distros have all gone with default-pie and
default-ssp, it probably got ignored
- Added a _doc subpackage