d/patches: Add mandatory fields in reserved-memory node

On the R-Car Gen3 boards, u-boot will apply this reserved-memory node
directly on the Linux device-tree.

The linux kernel requires that the ranges, #address-cells
and #size-cells values must be set in the reserved-memory node.

Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
Change-Id: I7d7f048195b5499940e386f4744157f74b0df9f9