iwlwifi: fix semicolon.cocci warnings

drivers/net/wireless/intel/iwlwifi/iwl-io.c:243:2-3: Unneeded semicolon

 Remove unneeded semicolon.

Generated by: scripts/coccinelle/misc/semicolon.cocci

CC: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>