Option to set a custom baud rate

[ChocolateLoverRaj]

I want to set the baud rate to 115200, but that is not possible rn cuz the init fn assumes a different baud rate. #25 will accomplish this but it is out of date, and also I don't want to manually configure the other things besides baud rate.

~~Actually I won't be using this since it's working on my Chromebook Jinlon with the default baud rate. Idk if the baud rate is actually getting used since Jinlon has a "16550 compatible" MMIO and it may just function the same regardless of baud rate.~~ nvm without setting correct baud rate it just displays a bunch of �, so I will be using this