iwlwifi: update 5000 ucode support to version 2 of API

enable iwl driver to support 5000 ucode having version 2 of API

Signed-off-by: Jay Sternberg <jay.e.sternberg@linux.intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>