The vm_numa_stat_key is declared in <linux/vmstat.h> but this is
currently not included in mm/page_alloc.c so include it to fix
the following sparse warning:

mm/page_alloc.c:165:1: warning: symbol 'vm_numa_stat_key' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
---
 mm/page_alloc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d49c254174da..58aa960a8dd0 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -54,6 +54,7 @@
 #include <linux/delayacct.h>
 #include <linux/cacheinfo.h>
 #include <linux/pgalloc_tag.h>
+#include <linux/vmstat.h>
 #include <asm/div64.h>
 #include "internal.h"
 #include "shuffle.h"
-- 
2.37.2.352.g3c44437643