In the fs_readdir_empty_dir test, the uv_fs_readdir() request is
cleaned up after calling uv_fs_closedir(). However, the readdir
request should be cleaned up before calling uv_fs_closedir().
Fixes: https://github.com/libuv/libuv/issues/2496
PR-URL: https://github.com/libuv/libuv/pull/2497
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>