arm: dts: rmobile: r8a774a1: Synchronize DTs with Linux 5.10

DTS files apart from r8a774a1-hihope-rzg2m-u-boot.dts and
r8a774a1-u-boot.dtsi have been imported from linux 5.10
commit 2c85ebc57b3e1817 ("Linux 5.10").

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>