60 sorts higher than the other drivers (evdev has 10, synaptics, wacom and
others have 50) so we keep the same order.

This is part of a two-step solution, the other half is renaming the
xf86-input-wacom's config snippet to sort higher than libinput's.

Currently libinput picks up devices that are (for now) destined to the wacom
driver. Since the wacom driver is more of a leaf package than libinput, the
best option here is to make the wacom driver sort higher and let users
uninstall it when not needed. To avoid crowding the 90-* space where users
usually have custom config snippets, drop libinput down to 60 and bump wacom
up.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Acked-by: Jason Gerecke <jason.gerecke@wacom.com>