iwl4965: reset firmware after rfkill off

Using rfkill switch can make firmware unstable, what cause various
Microcode errors and kernel warnings. Reseting firmware just after
rfkill off (radio on) helped with that.

Resolve:
https://bugzilla.redhat.com/show_bug.cgi?id=977053

Reported-and-tested-by: Justin Pearce <whitefox@guardianfox.net>
Cc: stable@vger.kernel.org
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlegacy/4965-mac.c

@@ -4460,12 +4460,12 @@ il4965_irq_tasklet(struct il_priv *il)
 		 * is killed. Hence update the killswitch state here. The
 		 * rfkill handler will care about restarting if needed.
 		 */
-		if (!test_bit(S_ALIVE, &il->status)) {
-			if (hw_rf_kill)
-				set_bit(S_RFKILL, &il->status);
-			else
-				clear_bit(S_RFKILL, &il->status);
+		if (hw_rf_kill) {
+			set_bit(S_RFKILL, &il->status);
+		} else {
+			clear_bit(S_RFKILL, &il->status);
 			wiphy_rfkill_set_hw_state(il->hw->wiphy, hw_rf_kill);
+			il_force_reset(il, true);
 		}
 
 		handled |= CSR_INT_BIT_RF_KILL;

drivers/net/wireless/iwlegacy/common.c

@@ -4660,6 +4660,7 @@ il_force_reset(struct il_priv *il, bool external)
 
 	return 0;
 }
+EXPORT_SYMBOL(il_force_reset);
 
 int
 il_mac_change_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif,