Very basic bridge test: Set up two jails and test that they can pass IPv4
traffic over the bridge.
Reviewed by: melifaro, philip
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D23697
The netipsec and pf tests have a number of common test functions. These
used to be duplicated, but it makes more sense for them to re-use the
common functions.
PR: 236223