iwlwifi: Bug fix, CCMP with HW encryption with AGG

This patch fixes a bug in security. Enables CCMP HW encryption with
aggregations.

Signed-off-by: Max Stepanov <max.stepanov@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>