[PATCH libxkbcommon 0/2] Use flex and bison features

[Ran Benita]

These patches break yacc and lex compatibility mainly for removing the
global state from the parser, which I think is expected given that this
is a library.

This is my first patch to this list, so a few disclaimers:
- I hope it's the right list.
- I couldn't figure out the coding style (there seems to be use of
  *all* of them...), so I just tried to match the surroundings.
- I've been using libxkbcommon for some time and I have some more
  patches laying around. I can send them too if all is well.

Thanks,
Ran