[PATCH-RESEND] arm64/kexec: Fix missing extra range for crashkres_low.

[Yun Levi]

> Right, excluding crashkernel region may cause memory region splitting,
> so we need extra slot for that.
>
> Meanwhile, can you fix above code comment mess? Otherwise, this looks
> good to me.

Thanks! I'll remove the comment.

> Or we can add extra 2 slots like we do in x86, it just add another 16
> bytes temporarily.

Agree. I'll send the patch again by modifying nr_ranges' initialized value as 2.

Thanks!