How to detach a cleat with a warped screw
The simplest thing to do would be to buy new cleats.
If you're absolutely set on re-using this cleat, there is a tool called a screw extractor that lets you tap a small reverse-threaded hole in your existing screw. You'll need a power drill to use it. You will at minimum need new screws.
You might be able to fit a hacksaw blade between the cleat and sole to saw off the old bolt, but that seems less reliable.