UARTE: stopbits setting not exposed

[jnordholz]

Hi,

I'm working on a NRF52840-based design and need the UART configured as 8N2, but the UARTE driver doesn't expose CONFIG.STOP yet. I've created a simple PR (#353) that adds another parameter to the Uarte::new() constructor (next to the already existing "parity" parameter), but of course that's an incompatible API change.

Thanks for considering!

[jnordholz]

Ah, that's a 52840-specific feature (PR closed, sorry for the noise) - so then a cfg-guarded setter would be easier to integrate, however tweaking these settings usually requires disabling the peripheral, which is why these things are usually handled in the setup phase... I'll happily update my PR if you have an opinion where this should go.