lenovo/x201: Enable pcie lanes in wwan slot.

Change-Id: I7332eeed244877252074e661f1c256a69a9b428a
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/6482
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>