Fix Bug 23595729 dnet can't send out packet.

--- libdnet-libdnet-1.14/src/eth-dlpi.c.orig	2020-07-17 18:56:28.000000000 +0000
+++ libdnet-libdnet-1.14/src/eth-dlpi.c	2021-09-12 15:18:14.525536772 +0000
@@ -151,7 +151,7 @@
 	}
 #else
 	e->fd = -1;
-	snprintf(dev, sizeof(dev), "/dev/%s", device);
+	snprintf(dev, sizeof(dev), "/dev/net/%s", device);
 	if ((p = dev_find_ppa(dev)) == NULL) {
 		errno = EINVAL;
 		return (eth_close(e));
@@ -160,7 +160,7 @@
 	*p = '\0';
 
 	if ((e->fd = open(dev, O_RDWR)) < 0) {
-		snprintf(dev, sizeof(dev), "/dev/%s", device);
+		snprintf(dev, sizeof(dev), "/dev/net/%s", device);
 		if ((e->fd = open(dev, O_RDWR)) < 0)
 			return (eth_close(e));
 	}