refactor: Simplify qemu test script
Change directory to the location of the script, som files can be referenced relative to current directory. Override GOBIN, not GOPATH. Use basenc from coreutils for hex decoding, eliminating a dependency.
Change directory to the location of the script, som files can be referenced relative to current directory. Override GOBIN, not GOPATH. Use basenc from coreutils for hex decoding, eliminating a dependency.