rc.subr: don't require service to be enabled for status

For a service that sets an rcvar, there is a check whether it has been
enabled before the actual command is executed. If the check fails, one
gets a message to enable it and the returned exit status is 0.
However, this is usually undesirable for the status command, which is
a) supposed to check whether the service is running anyway and
b) returns a non-zero exit code if that is not the case.
Thus, skip the check for the status command.

PR: 272282
Reviewed by: emaste
MFC after: 3 days