ieee802154: it's IEEE 802.15.4, not ZigBee

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
diff --git a/net/ieee802154/dgram.c b/net/ieee802154/dgram.c
index 1a3334c..faecf64 100644
--- a/net/ieee802154/dgram.c
+++ b/net/ieee802154/dgram.c
@@ -1,5 +1,5 @@
 /*
- * ZigBee socket interface
+ * IEEE 802.15.4 dgram socket interface
  *
  * Copyright 2007, 2008 Siemens AG
  *