One True Awk upgrade

I'm upgrading the in-tree version of one-true-awk. Normally, this isn't a
problem, but there's a number of small differences I'm still trying
to figure out due to our... contorted history. Some of the revisions we had
in the vendor branch of our repo were accepted as-is, some completely, and
some not yet, We've also added bug fixes we've found, as well as fixes from
other BSDs, which has also caused at least one unexplained difference.

I should have it sorted out in the next day or so, but wanted to give a
heads up. I doubt anybody would notice, but each of the differences is
going to take a little time to sort out, chase back to the failing case,
work out with upstream if there's a bug or not, etc. There's also a small
window between r348513 and r348515 where the tree fails to build (due to
svn's commit subtree vs git's commit while tree differences).

Also, I've not tagged this as such, but my plans are to MFC to 12 next
week, and to 11 after 11.3R goes out the door.

Warner