[yocto] [meta-selinux] Jethro branch

[Philip Tricca]

Hey all,

meta-selinux has been tracking release branches for a while but we're
missing a Jethro. I've had a Jethro branch on my github fork for a bit.
It's pointing at 4c75d9cbc from master with no additional changes. Both
images build, boot, login and pass the basic smoke test. Seems like this
may be useful to others so I'll put it up in the yocto repo as well.

If anyone tests or uses it and runs into any problems with it please let
the list know.

Philip