ascend: share pool: Only memory of current process is allowed to u2k/k2u

ascend inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4EUVI


CVE: NA

Signed-off-by: Zhou Guanghui <zhouguanghui1@huawei.com>
Reviewed-by: Ding Tianhong <dingtianhong@huawei.com>
Reviewed-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>