cmd: zed: rc: drop "should be owned by root and 0600"

It doesn't matter, 0600 are Weird Permissions, and it's even weirder to
spec them for no reason ‒ it's perfectly fine if it's the usual 0:0 644,
or literally anything else, so long as unprivileged users can't edit it
(which (a) 644 accomplishes and (b) is at the administrator's
discretion, it's not unheard of to have adm users and having it
be 664 in that case is just as good; it's not our place to say)

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12544
Closes #13276