tramp (2.2.13.25.2); need ls --color=never

[Francesco Potortì]

When logging to a LibreELEC system I need ls --color=none.  The
LibreELEC is a stripped-down Linux system with non-standard file system
organisation, and it is not easy or immediate, nor useful in my opinion,
to try and change its defaults.  Apparently, it defults to interpreting
ls with colour.

I need a simple way to force ls --color=never when logging in to
LibreELEC.  The simple way I have found is to put this in my .emacs:

(defun tramp-get-ls-command (vec) "ls --color=never")

This is easy and probably even foolproof, as I think systems without a
GNU ls are in fact very rare.  However, maybe this use case may be a
reason to provide a generic way of forcing some commands on some
systems.