Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

pkgbase: Put devmatch in its own package

devmatch is useful on standalone machine but not on jails.
Put devinfo(8) and libdevinfo there too.

Differential Revision: https://reviews.freebsd.org/D36229

Move devmatch to sbin from usr/sbin.

Since we want to use devmatch in context before a split /,/usr system
has mounted /usr, move devmatch to /sbin.

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