iwlwifi: corrections to debug output of ucode statistics

remove duplicate header and clean up format so it is defined once
making changes consolicated ensuring consistancy of output.
no function change to date displayed.

Signed-off-by: Jay Sternberg <jay.e.sternberg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>