mm/damon/lru_sort: fix potential memory leak in damon_lru_sort_init()

damon_lru_sort_init() returns an error when damon_select_ops() fails
without freeing 'ctx' which allocated before.  This commit fixes the
potential memory leak by freeing 'ctx' under the situation.

Link: https://lkml.kernel.org/r/20220714170458.49727-1-sj@kernel.org
Fixes: 40e983cc ("mm/damon: introduce DAMON-based LRU-lists Sorting")
Signed-off-by: NSeongJae Park <sj@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

mm/damon/lru_sort.c

@@ -524,8 +524,10 @@ static int __init damon_lru_sort_init(void)
 	if (!ctx)
 		return -ENOMEM;
 
-	if (damon_select_ops(ctx, DAMON_OPS_PADDR))
+	if (damon_select_ops(ctx, DAMON_OPS_PADDR)) {
+		damon_destroy_ctx(ctx);
 		return -EINVAL;
+	}
 
 	ctx->callback.after_wmarks_check = damon_lru_sort_after_wmarks_check;
 	ctx->callback.after_aggregation = damon_lru_sort_after_aggregation;