iwlagn: move iwl_enable_rfkill_int and kill iwl-helpers.h

Move iwl_enable_rfkill_int to iwl-core.h, and remove the empty
iwl-helpers.h

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-6000.c

@@ -40,7 +40,6 @@
 #include "iwl-core.h"
 #include "iwl-io.h"
 #include "iwl-agn.h"
-#include "iwl-helpers.h"
 #include "iwl-agn-hw.h"
 #include "iwl-trans.h"
 #include "iwl-shared.h"