rc: remove redundant upercase dependencies

[trasz]

Summary

Since the UPPERCASE rc scripts follow a predefined ordering,
remove cases where a script would specify more than one of them.
Also explicitly enforce ordering between NETWORKING and FILESYSTEMS,
and SERVERS and NETWORKING - the ordering was documented to exist,
and existed in practice, but was not explicit.

This should be a no-op, but might not be - it looks like the sorting done
by rcorder(8) isn't particularly stable.