csh: Remove hardlink /.cshrc

[manu]

Summary

Remove this historical artifact.
csh will try to use /.csrch if the user has no home directory defined which
is rather unlikely (To be exact if the concatenation of $HOME and "/.cshrc"
fail which is the same thing).

Also, with this change pkg will happily handle 3way merge for /root/.cshrc

Sponsored by: Beckhoff Automation GmbH & Co. KG

[emaste]

Tag it for Relnotes, I'd say

[imp]

I think this is a good idea.

Historically, root's home directory was /. Later, it moved to /root.
I believe this hard link originated in that move.
There were times when things were so messed up that the system was confused about home directories, so would default to /, and so this would give users something other than a bare shell. IIRC (and this is fuzzy) this was most often the root user in the early days, but became other users for when the NAS was down. But maybe that's an accidental side effect.
I've not done a full, deep dive, but root looks to have moved around in 4.4BSD time frame. But 30 years is long enough to allow for a transition to complete.

This same niggle tripped up mergemaster. IIRC from that experience, there were more than one of these files. But it looks like 4.4BSD also had .profile, but that was moved to /bin/sh when brad broke up the giant etc Makefile...