Use GPIO pins for boot input mode select

[rmaccrimm]

Problem

After changing profiles, the physical buttons used to select input mode may change on the next boot due to different pin mappings. Often I just end up doing a lot of guess-and-checking as I restart the device until I get the right input mode.

Solution

I've implemented a fairly simple alternative in which you enable a GPIO input mode select flag and then configure a list of mappings from pin numbers to input modes. It adds the following new fields to GamepadOptions

Do you plan to work on this feature yourself?

Yes, I've already got the basic functionality working. If there aren't any problems/concerns around adding this I can figure something out for the web config.

[TheTrainGoes]

The is an interesting thing, also something that we have talked about before not just from the booting perspective but also other shortcuts and the FN layer.

Overall I agree that this is a net-positive change and something we can look at less as connecting boot modes to buttons and more as looking at them as connected to GPIO which is more consistent with our current setup.