This is a tool that communicates with FEXLoader/FEXInterpreter to automatically mount
squashfs based rootfs files on execve.
This tool will launch automatically if you have a squashfs based rootfs selected.
Once the rootfs is mounted, it will watch for the parent FEX processe to completely exit.
Once the parent FEX exits it will unmount and cleanup after itself.
This tool has a dependency on your host having FUSE, fusermount, and squashfuse applications.
If anything goes wrong in the bringup process then it propagates the erro up the chain and will
let FEX know that it couldn't mount.