smc91x: fix build breakage from the SMC_GET_MAC_ADDR API upgrade

Cc: Jeff Garzik <jeff@garzik.org>
Cc: Deepak Saxena <dsaxena@plexity.net>
Cc: Nicolas Pitre <nico@cam.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>