Consistently use AF_UNIX over AF_LOCAL

As these constants have the same value 1, let's use and print only one
of them, e.g. AF_UNIX.

* xlat/addrfams.in (AF_LOCAL): Remove.
* tests/net-accept-connect.c (main): Replace AF_LOCAL with AF_UNIX.
* tests/net-y-unix.c: Likewise.
* tests/net-yy-unix.c: Likewise.
* tests/netlink_unix_diag.c: Likewise.
diff --git a/tests/netlink_unix_diag.c b/tests/netlink_unix_diag.c
index b91cbbb..269adc6 100644
--- a/tests/netlink_unix_diag.c
+++ b/tests/netlink_unix_diag.c
@@ -138,8 +138,8 @@
 	close(1);
 
 	(void) unlink(SUN_PATH);
-	if (socket(AF_LOCAL, SOCK_STREAM, 0))
-		perror_msg_and_skip("socket AF_LOCAL");
+	if (socket(AF_UNIX, SOCK_STREAM, 0))
+		perror_msg_and_skip("socket AF_UNIX");
 	if (bind(0, (struct sockaddr *) &addr, len))
 		perror_msg_and_skip("bind");
 	if (listen(0, 5))