feat(rcar): add support for Renesas R-Car S4 / V4H / V4M

Add support for Renesas R-Car S4 / V4H / V4M , which are Gen4 SoC.
Unlike Gen3, the Gen4 uses only TFA BL31 during boot.

Change-Id: I63907da539c19f81628186692f24e43e5d7d436c
Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
7 files changed