Add a libc wrapper for statx(2).

Bug: http://b/127675384
Bug: http://b/146676114
Test: treehugger
Change-Id: I844edc12f62717e579870a040cf03dfe60dc280b
diff --git a/libc/include/bits/fortify/stat.h b/libc/include/bits/fortify/stat.h
index e92e6ac..2d42a51 100644
--- a/libc/include/bits/fortify/stat.h
+++ b/libc/include/bits/fortify/stat.h
@@ -26,9 +26,7 @@
  * SUCH DAMAGE.
  */
 
-#ifndef _SYS_STAT_H_
-#error "Never include this file directly; instead, include <sys/stat.h>"
-#endif
+#pragma once
 
 mode_t __umask_chk(mode_t) __INTRODUCED_IN(18);
 mode_t __umask_real(mode_t mode) __RENAME(umask);