usb/dev-hid: Modified usb-tablet category from Misc to Input

usb-tablet device was wrongly assigned to Misc category

Reported-by: Markus Armbruster <armbru@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>