On Marvell MVEBU SoCs internal registers are usually remapped from reset
default. While Dove and Kirkwood always had their registers remapped,
some Armada 370 and XP where shipped with bootloaders that did not remap
them.

On Barebox these registers are remapped early and on all MVEBU SoCs, so
provided DTs should always reflect that in their mbus ranges property.

This patch registers a fixup for DTBs and allows individual SoCs to add
specific remap ranges to the fixup list. The fixup is registered on
pure_initcall to even allow to fixup pbl or appended DTBs.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>