[U-Boot] [U-Boot, v8, 20/30] efi: Tidy up device-tree-size calculation in copy_fdt()

[Alexander Graf]

> This is a bit confusing at present since it adds 4KB to the pointer, then
> rounds it up. It looks like a bug, but is not.
> 
> Move the 4KB addition into a separate statement and expand the comment.
> 
> Signed-off-by: Simon Glass <sjg at chromium.org>

Thanks, applied to efi-next

Alex