When porting lavapipe to the common sync framework, I stole the dummy
sync signal_for_memory idea from RADV but didn't actually do it
correctly. Unless you set wsi_device::signal_semaphore_with_memory and
wsi_device::signal_fence_with_memory, it doesn't actually signal
anything. If you do set those, it works but also results in dummy
syncs being created for present fences which we see as signals. We
could choose to just skip those like RADV does but that's too magic.
Instead, have our own AcquireNextImage2() again which sets dummy syncs.
Fixes: 3b547a9b58 ("lavapipe: Switch to the common sync framework")
Reviewed-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15774>
dbfb0b4989