mac802154: add llsec decryption method

Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mac802154/llsec.h b/net/mac802154/llsec.h
index 083055b..950578e 100644
--- a/net/mac802154/llsec.h
+++ b/net/mac802154/llsec.h
@@ -103,5 +103,6 @@
 				 const struct ieee802154_llsec_seclevel *sl);
 
 int mac802154_llsec_encrypt(struct mac802154_llsec *sec, struct sk_buff *skb);
+int mac802154_llsec_decrypt(struct mac802154_llsec *sec, struct sk_buff *skb);
 
 #endif /* MAC802154_LLSEC_H */