HID: wacom: devres manage the shared data too

wacom_release_shared_data() and wacom_remove_shared_data() are moved up
so they can be referenced in wacom_add_shared_data().

There is no point in explicitly setting wacom_wac1->shared->type to 0 in
wacom_wireless_work() (plus this would give an oops).

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>