f2fs: quota: do not mount as RDWR without QUOTA if quota feature enabled

If quota feature is enabled, quota is on by default. However, if
CONFIG_QUOTA is not built in kernel, dquot entries will not get updated,
which leads to quota inconsistency.

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>