Commit 1 of 2 to fix ffsinfo(8) for UFS2.

Commit 1 of 2 to fix ffsinfo(8) for UFS2.

Update ffsinfo(8) to use new UFS2 support in the growfs(8) debugging
functions.  Largely consists of renaming fields and types to be aware
of the UFS1/UFS2 distinction, relying on libufs(3) to open and sanity
check the device/file/label accessed.

Since libufs(3) now handles label/UFS interactions, remove -L argument.

Note: when submitted, this patch had substantial style changes.  I've
attempted to remove the restyling from the patch to separate the
functional and style changes.

Submitted by:	Lukas Ertl <l.ertl@univie.ac.at>
PR:		bin/53517