HID: wacom: Move Graphire raport header check.

That check is valid only for Wacom Graphire, as the device raports always
start with 0x03. Intuos4 WL high-speed raports begin with 0x04, so
the check would be filtering out valid reports.

Signed-off-by: Przemo Firszt <przemo@firszt.eu>
Acked-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>