mm: mempolicy: Make MPOL_LOCAL a real policy

Make MPOL_LOCAL a real and exposed policy such that applications that
relied on the previous default behaviour can explicitly request it.

Requested-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
diff --git a/include/uapi/linux/mempolicy.h b/include/uapi/linux/mempolicy.h
index 23e62e0..3e835c9 100644
--- a/include/uapi/linux/mempolicy.h
+++ b/include/uapi/linux/mempolicy.h
@@ -20,6 +20,7 @@
 	MPOL_PREFERRED,
 	MPOL_BIND,
 	MPOL_INTERLEAVE,
+	MPOL_LOCAL,
 	MPOL_MAX,	/* always last member of enum */
 };