mm: page_cgroup needs linux/vmalloc.h for vmalloc_node()/vfree().

Trivial build fix for:

CC mm/page_cgroup.o
mm/page_cgroup.c: In function 'init_section_page_cgroup':
mm/page_cgroup.c:111: error: implicit declaration of function 'vmalloc_node' mm/page_cgroup.c:111: warning: assignment makes pointer from integer without a cast mm/page_cgroup.c: In function '__free_page_cgroup':
mm/page_cgroup.c:140: error: implicit declaration of function 'vfree' make[1]: *** [mm/page_cgroup.o] Error 1
make: *** [mm/page_cgroup.o] Error 2

Signed-off-by Paul Mundt <[email protected]>

---

 mm/page_cgroup.c |    1 +
 1 file changed, 1 insertion(+)

mm/page_cgroup.c +1 -0

index 5d86550..78242b4 100644
@@ -5,6 +5,7 @@
 #include <linux/page_cgroup.h>
 #include <linux/hash.h>
 #include <linux/memory.h>
+#include <linux/vmalloc.h>
 
 static void __meminit
 __init_page_cgroup(struct page_cgroup *pc, unsigned long pfn)