b43: correctly display longer chipsets ids

Some of the newer Broadcom chipsets have longe names like BCM43224,
BCM43225, etc. However Broadcom decided to keep using u16 for storing
them. Use %X or %d depending on chip_id value to avoid BCMA8D8, etc.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>