kbuild: install kernel-page-flags.h

commit 9295b7a0 upstream.

Programs using /proc/kpageflags need to know about the various flags.  The
<linux/kernel-page-flags.h> provides them and the comments in the file
indicate that it is supposed to be used by user-level code.  But the file
is not installed.

Install the headers and mark the unstable flags as out-of-bounds.  The
page-type tool is also adjusted to not duplicate the definitions
Signed-off-by: Ulrich Drepper <drepper@gmail.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: adjust context; drop change to missing tools/vm/]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

include/linux/Kbuild

@@ -224,6 +224,7 @@ header-y += kd.h
 header-y += kdev_t.h
 header-y += kernel.h
 header-y += kernelcapi.h
+header-y += kernel-page-flags.h
 header-y += keyboard.h
 header-y += keyctl.h
 header-y += l2tp.h

include/linux/kernel-page-flags.h

@@ -31,6 +31,8 @@
 
 #define KPF_KSM			21
 
+#ifdef __KERNEL__
+
 /* kernel hacking assistances
  * WARNING: subject to change, never rely on them!
  */
@@ -43,4 +45,6 @@
 #define KPF_ARCH		38
 #define KPF_UNCACHED		39
 
+#endif /* __KERNEL__ */
+
 #endif /* LINUX_KERNEL_PAGE_FLAGS_H */