mac802154: rx: document ieee802154_rx() context requirement

This patch is similar like d20ef63d32461332958661df73e21c0ca42601b0
("mac80211: document ieee80211_rx() context requirement"). The
netif_receive_skb call requires with softirqs disabled. This patch
adds a warning if softirqs are pending while calling ieee802154_rx.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/mac802154/rx.c

@@ -61,6 +61,8 @@ fail:
 
 void ieee802154_rx(struct ieee802154_hw *hw, struct sk_buff *skb)
 {
+	WARN_ON_ONCE(softirq_count() == 0);
+
 	mac802154_subif_rx(hw, skb);
 }
 EXPORT_SYMBOL(ieee802154_rx);