tools/vm/page_owner_sort.c: adjust the indent in is_need()

I noticed one more indentation than necessary in is_need().

Link: https://lkml.kernel.org/r/20220717195506.7602-1-caoyixuan2019@email.szu.edu.cnSigned-off-by: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>