iwl3945: Add restart_fw module parameter

In order to be in sync with the agn code, we're ading a fw_restart3945 module
parameter to iwl3945.

Signed-off-by: Samuel Ortiz <samuel.ortiz@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>