Update OBS Plugin (420 -> 422)

[pthrasher]

At some point the format supplied by the hd60s must have changed as it's now UYVY 422 instead of YUV420P.

This is a simple change to fix that. I know you said you weren't going to support the obs plugin, but I'm using it, fixed it, and thought I'd contribute those changes back. :-) Next step for me is going to try to interface with the hd60s directly using their own drivers.