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

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: 40e983cca927 ("mm/damon: introduce DAMON-based LRU-lists Sorting")
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>