ssb: fix cardbus slot in hostmode

ssb supports one extra device on the cardbus. This results in two
devices in total, one beeing the host controller itself and the other
the external device connected to the hostcontroller over cardbus.

This makes the cardbus slot work on the Linksys WRT150N.

Reported-by: Aaron Z <aaronz@pls-net.org>
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>