As part of moving to using OF_UPSTREAM and so the upstream dt-bindings
headers we have a number of these headers that are in our include
directory and are currently identical to the versions in dts/upstream.
We can remove these now to prevent future conflicts.

Signed-off-by: Tom Rini <trini@konsulko.com>

The EK874 development kit from Silicon Linux is made of CAT874 (the main
board) and CAT875 (the sub board that goes on top of CAT874).

This patch adds the required board support to boot Si-Linux EK874 board
based on R8A774C0 SoC.

DTS files apart from r8a774c0-ek874-u-boot.dts and r8a774c0-u-boot.dtsi
have been imported from Linux kernel 5.11 commit f40ddce88593
("Linux 5.11").

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