Basic support for the Renesas Ebisu board based on R-Car E3:
  - Memory,
  - Main crystal,
  - Serial console,
Signed-off-by: NTakeshi Kihara <takeshi.kihara.df@renesas.com>
[shimoda: rebase and add SPDX-License-Identifier]
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NMarek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>