keyboard-fw: allow meta key to remap soft keys

Created by: asmadeus

This might (or might not) work to remap keys as another when meta is pressed e.g. meta+up would do pageup as I'm used to.

If this works it'd be easy to add more e.g. meta+left = home, meta+right = end etc

Obviously untested as I have no idea how I could test this before receiving mine, so if it doesn't work right away I'd say this would be just as well to leave the PR open until then for me to debug, it's not like I would benefit from this before :P

But at least it compiles, and it used to make sense to me at the time (I remember I wasn't 100% happy with this for some reason, but forgot why :/)

Cheers & take care of yourself for the last few weeks of rush :)