bcma: register NAND and QSPI cores early

On Northstar (ARM arch) we will use MTD subsystem to access NVRAM and
SPROM. To get access to flash device we need to register these cores
first.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>