This patch fix iwl_mac_set_key function changed in patch
"mac80211: clean up set_key callback"

1. removing 'static' const u8 *addr' that can possible cause
conflict when two or more NICs are present in the system.
2. simplifying functions
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NReinette Chatre <reinette.chatre@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>