feat: 支持setns接口

BREAKING CHANGE:
支持setns接口对外变更:
1.新增setns接口

Close #I6D9Y0

Signed-off-by: zhushengle <zhushengle@huawei.com>
Change-Id: I9aacf9e5b8463e8e6c743a0041a5b2b18fdb0e12

testsuites/unittest/container/full/It_pid_container_010.cpp

@@ -35,6 +35,7 @@ static int ChildFun(void *p)
     int ret;
     int currGid = getpgrp();
     if (currGid != CONTAINER_FIRST_PID) {
+        printf("ChildFun pid %d currGid %d\n", getpid(), currGid);
         return EXIT_CODE_ERRNO_1;
     }