!2546 memcg swap qos: add ability to disable memcg swap

Merge Pull Request from: @hitmoon 
 
issue: https://gitee.com/openeuler/kernel/issues/I8AQ5E 
 
Link:https://gitee.com/openeuler/kernel/pulls/2546

 

Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>