timeout: Move from /usr/bin to /bin

timeout(1) is used by /etc/rc.d/zfskeys. Unfortunately, having
timeout(1) installed in /usr/bin causes problems when /usr is an
encrypted ZFS partition.

Implementing timeout(1) in sh(1) is not trivial. A more elegant solution
is to move timeout(1) to /bin so that it is available to early services
in the boot process.

PR: 265221
Reviewed by: allanjude, des, imp
Approved by: allanjude, des, imp
Reported by: Ivan <r4@sovserv.ru>
Fixes: 33ff39796ffe Add zfskeys rc.d script for auto-loading encryption keys
Relnotes: yes
Sponsored by: Modirum MDPay
Sponsored by: Klara Inc.
Differential Revision: https://reviews.freebsd.org/D38344

(cherry picked from commit e7ab133648a168c4bf7c11da840663c5581771d8)