nsd: add stub implementation

services/nsd/main.c

@@ -1,4 +1,10 @@
+#include <errno.h>
+#include <magenta/log.h>
+#include <stdio.h>
+#include <string.h>
+
 int main(void)
 {
+	printf("nsd running %s\n", strerror(ENOTSUP));
 	return 0;
 }