This fixes compile error when nr_free_pages() from linux/swap.h
expands to global_page_state(NR_FREE_PAGES), but linux/vmstat.h isn't
included to declare global_page_state().
Signed-off-by: NJesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <mikael.starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>