ARM: dts: vt8500: Move memory nodes to board dts and fix addr/size

ARM: dts: vt8500: Move memory nodes to board dts and fix addr/size

VIA/WonderMedia SoCs don't have on-chip memory, so their memory
nodes are better placed in per-board dts rather than per-SoC dtsi.

Move them accordingly, and also add correct node addresses and
sizes for each of the boards. Some boards were also available with
more memory than included in this commit - those would need a
separate DT or an appropriate kernel cmdline argument to reflect it,
as the bootloader on these devices doesn't handle DT at all nor does
it any runtime discovery of available memory size.

Signed-off-by: Alexey Charkov <alchark@gmail.com>
Link: https://lore.kernel.org/r/20250515-wmt-dts-updates-v2-2-246937484cc8@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>