sys/stat.h required for macros lik S_IWUSR

Index: mono/utils/mono-state.c
--- mono/utils/mono-state.c.orig
+++ mono/utils/mono-state.c
@@ -8,6 +8,7 @@
  * (C) 2018 Microsoft, Inc.
  *
  */
+#include <sys/stat.h>
 #include <config.h>
 #include <glib.h>
 #include <mono/utils/mono-state.h>