mm/damon/core-test: fix wrong expectations for 'damon_split_regions_of()'

mainline inclusion
from mainline-5.15
commit 2e014660
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4GVMK
CVE: NA

-------------------------------------------------
Kunit test cases for 'damon_split_regions_of()' expects the number of
regions after calling the function will be same to their request
('nr_sub').  However, the requested number is just an upper-limit,
because the function randomly decides the size of each sub-region.

This fixes the wrong expectation.

Link: https://lkml.kernel.org/r/20211028090628.14948-1-sj@kernel.org
Fixes: 17ccae8b ("mm/damon: add kunit tests")
Signed-off-by: NSeongJae Park <sj@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 2e014660)
Signed-off-by: NYue Zou <zouyue3@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

mm/damon/core-test.h

@@ -219,14 +219,14 @@ static void damon_test_split_regions_of(struct kunit *test)
 	r = damon_new_region(0, 22);
 	damon_add_region(r, t);
 	damon_split_regions_of(c, t, 2);
-	KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 2u);
+	KUNIT_EXPECT_LE(test, damon_nr_regions(t), 2u);
 	damon_free_target(t);
 
 	t = damon_new_target(42);
 	r = damon_new_region(0, 220);
 	damon_add_region(r, t);
 	damon_split_regions_of(c, t, 4);
-	KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 4u);
+	KUNIT_EXPECT_LE(test, damon_nr_regions(t), 4u);
 	damon_free_target(t);
 	damon_destroy_ctx(c);
 }