This fixes a NULL pointer dereference that can occur when the
ucode is not loaded at the time __iwl_up is called.

The problem was reported at http://kerneloops.org/raw.php?rawid=2765&msgid=Signed-off-by: NReinette Chatre <reinette.chatre@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>