test-aio failure with liburing

[Cole Robinson]

Using qemu.git master with liburing-devel installed. 100% reproducible
test failure for me

$ uname -r
5.6.0-0.rc5.git0.2.fc32.x86_64
$ rpm -q liburing
liburing-0.5-1.fc32.x86_64

$ ./tests/test-aio
# random seed: R02S70cd9b447cc815ed3194d31e97371542
1..28
# Start of aio tests
ok 1 /aio/acquire
ok 2 /aio/external-client
# Start of bh tests
ok 3 /aio/bh/schedule
ok 4 /aio/bh/schedule10
ok 5 /aio/bh/cancel
ok 6 /aio/bh/delete
ok 7 /aio/bh/flush
# Start of callback-delete tests
ok 8 /aio/bh/callback-delete/one
ok 9 /aio/bh/callback-delete/many
# End of callback-delete tests
# End of bh tests
# Start of event tests
ok 10 /aio/event/add-remove
ok 11 /aio/event/wait
**
ERROR:tests/test-aio.c:374:test_flush_event_notifier: assertion failed:
(aio_poll(ctx, false))
Bail out! ERROR:tests/test-aio.c:374:test_flush_event_notifier:
assertion failed: (aio_poll(ctx, false))
Aborted (core dumped)


Configuring with --disable-linux-io-uring makes the failure go away

I saw this patch about another uring test-aio failure, but that patch is
already in git master, and the failure is different:
https://lists.gnu.org/archive/html/qemu-devel/2020-03/msg06299.html


Thanks,
Cole