QEMU does not close listening socket for incoming migration when post-copy migration breaks
Description of problem:
QEMU keeps listening on the incoming port even after breaking a post-copy
migration using "migrate-pause" QMP command. And even once migration is
finished after recovering it "migrate-recover" using a different port number.
If "migrate-recover" is called with a URI specifying the original port (which
is still in LISTEN state), QEMU reports "Failed to find an available port:
Address already in use".
Steps to reproduce:
1. start migration
2. wait for the first iteration to finish
3. switch to post-copy using "migrate-start-postcopy"
3. break migration with "migrate-pause"
4. check lsof -p $QEMU_PID
Additional information: