mm: drop zap_details::check_swap_entries

detail == NULL would give the same functionality as
.check_swap_entries==true.

Change-Id: Iddb5499d069ac76126812c0296389409215cda9a
Link: http://lkml.kernel.org/r/20170118122429.43661-2-kirill.shutemov@linux.intel.com


Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-Commit: 3e8715fdc03e8df4d26d8e436166e44e3e416d3b
Git-Repo: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git


Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>