Add support for the MMC2/SDIO WiFi Libertas (Marvell) module available
on the CM-T3530 SOM.

Cc: Dmitry Lifshitz <lifshitz@compulab.co.il>
Cc: Igor Grinberg <grinberg@compulab.co.il>
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>