ipc: stop mp control thread on cleanup

ipc: stop mp control thread on cleanup

When calling rte_eal_cleanup, the mp channel cleanup routine only sets
mp_fd to -1 leaving the rte_mp_handle control thread running.
This control thread can spew warnings on reading on an invalid fd.
This is especially noticed with ASAN enabled.

To handle this situation, set mp_fd to -1 to signal the control thread
it should exit, but since this thread might be sleeping on the socket,
cancel the thread too.

Fixes: 85d6815fa6d0 ("eal: close multi-process socket during cleanup")
Cc: stable@dpdk.org
Reported-by: Owen Hilyard <ohilyard@iol.unh.edu>
Signed-off-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>