comedi: use menuconfig for main Comedi menu

Bring the Comedi menu in line with most other device drivers
by using "menuconfig" instead of "config" for the top-level entry.
This also fixes a menu presentation issue with xconfig.

Fixes: ed9eccbe ("Staging: add comedi core")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: David Schleef <ds@schleef.org>
Cc: Shawn Bohrer <shawn.bohrer@gmail.com>
Cc: Frank Mori Hess <fmhess@users.sourceforge.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20230110064844.18533-1-rdunlap@infradead.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>