Fix liveness of buf

So that domain can point to it.

l2tpns.c

@@ -4520,12 +4520,12 @@ static void stripdomain(char *host)
 	{
 		char *domain = 0;
 		char _domain[1024];
+		char buf[1024];
 
 		// strip off domain
 		FILE *resolv = fopen("/etc/resolv.conf", "r");
 		if (resolv)
 		{
-			char buf[1024];
 			char *b;
 
 			while (fgets(buf, sizeof(buf), resolv))