platform: generic: renesas: rzfive: Configure the PMA region

On the Renesas RZ/Five SoC by default we want to configure 128MiB of memory
ranging from 0x58000000 as a non-cacheable + bufferable region in the PMA
and populate this region as PMA reserve DT node with shared DMA pool and
no-map flags set so that Linux drivers requesting any DMA'able memory go
through this region.

PMA node passed to the above stack:

        reserved-memory {
            #address-cells = <2>;
            #size-cells = <2>;
            ranges;

            pma_resv0@58000000 {
                compatible = "shared-dma-pool";
                reg = <0x0 0x58000000 0x0 0x08000000>;
                no-map;
                linux,dma-default;
            };
        };

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Yu Chien Peter Lin <peterlin@andestech.com>
Reviewed-by: Anup Patel <anup@brainfault.org>