Update sysrc(8) manual to coincide with r252797:

Do not inherit $SYSRC_VERBOSE from operating environment. The concern is
that when a user (such as myself) which has SYSRC_VERBOSE=1 in his/her
~/.bash_profile or such that when they are told to execute a command like:

	hostname `sysrc -n hostname`

NOTE: To activate a recently configured hostname.

If $SYSRC_VERBOSE is set, then POLA is violated because the output of sysrc
is indirectly influenced (making for an inconsistent experience).
Update copyright/date on the back of r252798.
Update release info.
Whitespace.
Fix a typo.
Update date on the back of r252802.