iwl4965: use IWLWIFI_LEDS config variable

Fix error reported by Miles Lane <miles.lane@gmail.com>
Signed-off-by: NReinette Chatre <reinette.chatre@intel.com>
CC: Miles Lane <miles.lane@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-4965.h

@@ -1057,7 +1057,7 @@ struct iwl_priv {
 	struct iwl_rfkill_mngr rfkill_mngr;
 #endif
 
-#ifdef CONFIG_IWL4965_LEDS
+#ifdef CONFIG_IWLWIFI_LEDS
 	struct iwl4965_led led[IWL_LED_TRG_MAX];
 	unsigned long last_blink_time;
 	u8 last_blink_rate;