mm: trivial cleanups in vmscan.c

mm: trivial cleanups in vmscan.c

Utter trivia in mm/vmscan.c, mostly just reducing the linecount slightly;
most exciting change being get_scan_count() calling vmscan_swappiness()
once instead of twice.

Signed-off-by: Hugh Dickins <[email protected]>
Acked-by: KOSAKI Motohiro <[email protected]>
Acked-by: KAMEZAWA Hiroyuki <[email protected]>
Acked-by: Konstantin Khlebnikov <[email protected]>
Reviewed-by: Michal Hocko <[email protected]>
Cc: Johannes Weiner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>