It isn't necessarily safe to move the kernel (up to) 2MB higher in
memory. If the kernel is in a FIT, this may overwrite other data such as
the devicetree.
Use lmb (where available) as is done with other image relocations. Update
the return value to provide more specific information on failure.
Signed-off-by: Simon Glass <sjg@chromium.org>
695e4bef30