Poudriere friendly armv7 relases

Greetings,

Since it looks like we're going to retain at least armv7 for FreeBSD 14
(armv6 has been nominated for deprecation, but if it isn't deprecated, all
this applies to it).

I'd like to start making at least the base.tgz, etc available for armv7.
This would allow us to create armv7 poduriere jails without building from
source.

Is there some reason we're not doing this today? I know ISOs don't make a
lot of sense in the arm ecosystem, but having these artifacts would enable
poudriere binary install support.

Comments?

Warner