Add hotkey for reloading input configuration

[natdorshimer]

This adds a new hotkey that allows you to reload input configuration without having to alt-tab or leave the game.

I developed this more or less for personal use for my Frame1. Since I sometimes use different controller layouts for different characters it's a bit time consuming to alt tab and go to controller config and load a new profile. If I'm playing unranked sometimes they'll just leave before I have the chance to change it. This gives me the ability to programmatically load different profiles and then force dolphin to reload the input config through this hotkey since it won't do so automatically.

It's a bit of a niche use but it'd be really nice to have this in the main slippi build