Add minimal Windows SDK to build with standalone mingw64

SDKs/win/usr/include/sys/mman.h

@@ -0,0 +1,37 @@
+/* ===-- mman.h - stub SDK header for compiler-rt --------------------------===
+ *
+ *                     The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ * ===-----------------------------------------------------------------------===
+ *
+ * This is a stub SDK header file. This file is not part of the interface of
+ * this library nor an official version of the appropriate SDK header. It is
+ * intended only to stub the features of this header required by compiler-rt.
+ *
+ * ===-----------------------------------------------------------------------===
+ */
+
+#ifndef _SYS_MMAN_H_
+#define _SYS_MMAN_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+#define PROT_NONE 0
+#define PROT_READ 1
+#define PROT_WRITE 2
+#define PROT_EXEC 4
+
+#define _SC_PAGESIZE 8
+
+extern int mprotect (void *__addr, size_t __len, int __prot);
+
+#ifdef __cplusplus
+};
+#endif /* __cplusplus */
+
+#endif /*  _SYS_MMAN_H_ */