security/opendoas: new port: portable version of OpenBSD's doas

This is not an official port/project from OpenBSD!
OpenBSD doas does not support persist option for non OpenBSD systems,
OpenDoas originally made for Linux and MacOS does support this.
This port includes a patch for the OpenDoas to supports persist on FreeBSD.
This commit adds the OpenDoas as an alternative to sudo that supports persist.

PR: 279598
Approved by: Cathal O'Grady <fierceinbattle@gmail.com> (maintainer)