ntdll: Adds support for custom serial port baudrates on Mac

[Nathan Fearnley]

I've tried to update the code to be a little more cleanly separated, and
fixed the issue with BOOL. This code really just runs as an exception when
a custom baudrate is requested. Otherwise, it pretty much shares the same
code. If someone can suggest a better way to organize the code, I'd be
happy to implement it.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.winehq.org/pipermail/wine-patches/attachments/20141204/3a559d36/attachment-0001.html>