Use dracut's default squashfs image paths in ISOs

[davidcassany]

If we place the squashfs image to default path with the default name we might be able to work around a dracut upstream issue. Note we are currently seeing this issue in TW, Fedora (>= 38) and Ubuntu (>= 23.04).

Would be nice finding a way to circumvent this issue so we do not depend on dracut cutting a new release and landing this patch into the distros code stream.

The idea is set the ISO in a way that those two kernel parameters are no longer needed: rd.live.dir=/ rd.live.squashimg=rootfs.squashfs

dracut documentation states:

rd.live.dir=<path>
           Specifies the directory within the boot device where the
           squashfs.img or rootfs.img can be found. By default, this is
           /LiveOS.

rd.live.squashimg=<filename of SquashFS image>
           Specifies the filename for a SquashFS image of the root
           filesystem. By default, this is squashfs.img.

[davidcassany]

We can also try to submit to Tumbleweed and SLE the actual upstream patch

[davidcassany]

This is no longer needed thanks to openSUSE/dracut#311 Closing