iwlwifi: add support for 22560 devices

Add support for the new 22560 family of devices and, while at it,
reorganize the 22000 family so it fits better with the new one.

Signed-off-by: Golan Ben Ami <golan.ben.ami@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>