Fix typo interrest[ing|ed] => interest[ing|ed]

Fix typos with interrest*.

Signed-off-by: Thomas Weber <weber@corscience.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/net/wan/hdlc.c b/drivers/net/wan/hdlc.c
index 9937bba..5d4bb61 100644
--- a/drivers/net/wan/hdlc.c
+++ b/drivers/net/wan/hdlc.c
@@ -109,7 +109,7 @@
 		return NOTIFY_DONE; /* not an HDLC device */
 
 	if (event != NETDEV_CHANGE)
-		return NOTIFY_DONE; /* Only interrested in carrier changes */
+		return NOTIFY_DONE; /* Only interested in carrier changes */
 
 	on = netif_carrier_ok(dev);