问题描述：
在系统中创建一个孤儿进程，系统最后没有回收掉创建的这个孤儿进程。并强行使用kill -9 命令去杀这个孤儿进程也是杀不掉的，依旧在系统中有残留。

测试模块：process_posix
测试版本:https://hm-verify.obs.cn-north-4.myhuaweicloud.com/version/Daily_Version/20210601_033440/version-Daily_Version-20210601_033440-hispark_aries.tar.gz
测试用例:PidTest.testOrphanProcess
测试LOG：
Repeating all tests (iteration 49) . . .

Note: Google Test filter = PidTest.testOrphanProcess
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from PidTest
[ RUN ] PidTest.testOrphanProcess
parent process id:16
sub parent process id:53
orphane process id:21
before while child child 1
after while child child 1
child child exit 2
before while paret 2
[ OK ] PidTest.testOrphanProcess (206 ms)
[----------] 1 test from PidTest (210 ms total)

[----------] Global test environment tear-down
Gtest xml output finished
[==========] 1 test from 1 test case ran. (240 ms total)
[ PASSED ] 1 test.

Repeating all tests (iteration 50) . . .

Note: Google Test filter = PidTest.testOrphanProcess
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from PidTest
[ RUN ] PidTest.testOrphanProcess
parent process id:16
sub parent process id:53
[ERR]No idle PCB in the system!
======== Fork Error! =========
../../../test/xts/acts/kernel_lite/process_posix/src/PidTest.cpp:107: Failure
Expected equality of these values:
exitCode
Which is: 1
0
target process should exited 0.

before while paret 1
[441676][W:751]{hmac_rx_lan_frame_classify:user=1,type=4,len=60}[0~3dhcp 4arp_req 5arp_rsp 6eapol]