I'm a bit confused about this patch.
I can see how api-horribly-long-name.StartThreadpoolIo goes to kernel32.StartThreadpoolIo which then goes to ntdll.TpStartAsyncIoOperation.
But as far as I can tell Wine's ntdll is not exporting TpStartAsyncIoOperation(): it's not mentioned anywhere in ntdll.spec. In fact, as far as I can tell it's not used anywhere.
Am I missing something?