bcma: gpio: register all 32 GPIOs on BCM53572

I've here a device detected as:
bcma: bus0: Found chip with id 0xD144, rev 0x01 and package 0x08
I couldn't find GPIO handling hw button until trying GPIO 20. It seems
BCM53572 also has 32 GPIOs.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>