cups: Add root,sys,wheel to system groups

cups: Add root,sys,wheel to system groups

The Cups documentation states:
The default contains "admin", "lpadmin", "root", "sys" and/or "system".
https://www.cups.org/doc/man-cups-files.conf.html#:~:text=SystemGroup

Add root and sys accordingly
Also add wheel group. This is required for systems with polkit support in order to
control the printer settings with cups-pk-helper.
Not only for gnome-control-center, but also when using plain system-config-printer on
a system with running polkit, cups-pk-helper would be a required rdepend.

Signed-off-by: Markus Volk <f_l_k@t-online.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 572fed0ac6dbcf5749e19c7b624826fc30cf301e)
Signed-off-by: Steve Sakoman <steve@sakoman.com>