ssb-pcmcia: Fix 32bit register access in early bus scanning

The scan function was using 32 bit access which does not
work on 16bit CF cards.

This patch corrects this by doing two 16 bit reads like
ssb_pcmcia_read32 already does.

mb -- Removed locking. That early in init there's no need for locking.

Signed-off-by: Martin Fuzzey <mfuzzey@gmail.com>
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>