iwlwifi: clean up iwl-commands.h

Do some cleanups here:
 * remove an unused prototype
 * remove some unused constants
 * clean up includes

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-sta.c b/drivers/net/wireless/iwlwifi/iwl-agn-sta.c
index cb6c230..cf5cc10 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn-sta.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-sta.c
@@ -26,7 +26,7 @@
  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  *
  *****************************************************************************/
-
+#include <linux/etherdevice.h>
 #include <net/mac80211.h>
 
 #include "iwl-dev.h"