mm: migrate: remove unused includes

random.h is not needed since commit 6c542ab7 ("mm/demotion: build
demotion targets based on explicit memory tiers"), all functions moved
into memory-tiers.

nsproxy.h is not needed since commit 228ebcbe ("Uninline
find_task_by_xxx set of functions"), no nsproxy, we only call
find_task_by_vpid() now.

hugetlb_cgroup.h is not needed since commit ab5ac90a ("mm, hugetlb: do
not rely on overcommit limit during migration"), move_hugetlb_state() is
called and it belongs to hugetlb.h, which is already included.

balloon_compaction.h, we have more general movable_operations for non-lru
movable page migration, so it could be dropped.

memremap.h, userfaultfd_k.h and oom.h are introduced for zone device page
migration, but all functions are moved into migrate_device.c, so no needed
anymore too.

Link: https://lkml.kernel.org/r/20240905152432.626877-1-wangkefeng.wang@huawei.comSigned-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/migrate.c

@@ -20,7 +20,6 @@
 #include <linux/pagemap.h>
 #include <linux/buffer_head.h>
 #include <linux/mm_inline.h>
-#include <linux/nsproxy.h>
 #include <linux/ksm.h>
 #include <linux/rmap.h>
 #include <linux/topology.h>
@@ -35,19 +34,13 @@
 #include <linux/syscalls.h>
 #include <linux/compat.h>
 #include <linux/hugetlb.h>
-#include <linux/hugetlb_cgroup.h>
 #include <linux/gfp.h>
 #include <linux/pfn_t.h>
-#include <linux/memremap.h>
-#include <linux/userfaultfd_k.h>
-#include <linux/balloon_compaction.h>
 #include <linux/page_idle.h>
 #include <linux/page_owner.h>
 #include <linux/sched/mm.h>
 #include <linux/ptrace.h>
-#include <linux/oom.h>
 #include <linux/memory.h>
-#include <linux/random.h>
 #include <linux/sched/sysctl.h>
 #include <linux/memory-tiers.h>
 #include <linux/pagewalk.h>