mm: memcontrol: remove the pgdata parameter of mem_cgroup_page_lruvec

mm: memcontrol: remove the pgdata parameter of mem_cgroup_page_lruvec

All the callers of mem_cgroup_page_lruvec() just pass page_pgdat(page) as
the 2nd parameter to it (except isolate_migratepages_block()).  But for
isolate_migratepages_block(), the page_pgdat(page) is also equal to the
local variable of @pgdat.  So mem_cgroup_page_lruvec() do not need the
pgdat parameter.  Just remove it to simplify the code.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Muchun Song <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Acked-by: Roman Gushchin <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Cc: Xiongchun Duan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>