ubuntu 22.04 compile error: control reaches end of non-void function [-Werror=return-type]

[MenglingD]

Compile error arised via g++/gcc version: g++ (Ubuntu 11.2.0-19ubuntu1) 11.2.0：

...
/var/lib/dkms/8812au/4.2.3/build/core/rtw_mp.c: In function ‘mp_xmit_packet_thread’:
/var/lib/dkms/8812au/4.2.3/build/core/rtw_mp.c:1182:1: error: no return statement in function returning non-void [-Werror=return-type]
 1182 | }

...

/var/lib/rrtl8812au/build/core/rtw_cmd.c:557:3: error: ‘return’ with no value, in function returning non-void [-Werror=return-type]
  557 |   return;

[MenglingD]

fix by kthread_complete_and_exit #244