renesas: rzg: Add support for DRAM initialization

Add support for initializing DRAM on RZ/G2M SoC.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Change-Id: I99f1a6971a061a44687af498d55306a93e4fc8f7
9 files changed