iwlwifi: clean up driver names for 1000/5000/6000

Align the driver names with official product names for 1000/5000/6000
series. This change mainly affects the debug messages show up in system
log. No functional changes.

Signed-off-by: Shanyu Zhao <shanyu.zhao@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>