mm/vmstat.c: fix outdated vmstat_text

7a9cdeb ("mm: get rid of vmacache_flush_all() entirely") removed the
VMACACHE_FULL_FLUSHES statistics, but didn't remove the corresponding
entry in vmstat_text.  This causes an out-of-bounds access in
vmstat_show().

Luckily this only affects kernels with CONFIG_DEBUG_VM_VMACACHE=y, which
is probably very rare.

Link: http://lkml.kernel.org/r/[email protected]
Fixes: 7a9cdeb ("mm: get rid of vmacache_flush_all() entirely")
Signed-off-by: Jann Horn <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Acked-by: Roman Gushchin <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Kemi Wang <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Ingo Molnar <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

mm/vmstat.c

@@ -1283,7 +1283,6 @@ const char * const vmstat_text[] = {
 #ifdef CONFIG_DEBUG_VM_VMACACHE
 	"vmacache_find_calls",
 	"vmacache_find_hits",
-	"vmacache_full_flushes",
 #endif
 #ifdef CONFIG_SWAP
 	"swap_ra",