arm64: dts: renesas: rcar-gen3: Add SoC model to comment headers

Make sure the R-Car Gen3 SoC model present is documented in the comment
header of each board DTS, on a single line. This makes it easier to
identify boards that are available with different SoC or SiP options.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/251569665d7d4f4ed4bbab7267ce2ddccdef33e5.1626261816.git.geert+renesas@glider.be

arm64: dts: renesas: r8a77961-ulcb: add HDMI Display support

This patch enables HDMI Display on M3ULCB with R-Car M3-W+.

Signed-off-by: Yuya Hamamachi <yuya.hamamachi.sx@renesas.com>
Link: https://lore.kernel.org/r/20210217090603.1517-1-yuya.hamamachi.sx@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

arm64: dts: renesas: Add support for M3ULCB with R-Car M3-W+

Add initial support for the Renesas M3ULCB board equipped with an R-Car
M3-W+ SiP with 8 (2 x 4) GiB of RAM.
To avoid build error on 'ulcb.dtsi', ssi2 is added into 'r8a77961.dtsi'.

Based on commit 92980759c1699a3c ("arm64: dts: renesas: Add support for
Salvator-XS with R-Car M3-W+").

Signed-off-by: Yuya Hamamachi <yuya.hamamachi.sx@renesas.com>
Link: https://lore.kernel.org/r/20200309064425.25437-3-yuya.hamamachi.sx@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>