arm64: dts: broadcom: Add reference to RPi 400

This adds a reference to the dts of the Raspberry Pi 400,
so we don't need to maintain the content in arm64.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenz@kernel.org>
Link: https://lore.kernel.org/r/1622981777-5023-8-git-send-email-stefan.wahren@i2se.comSigned-off-by: Nicolas Saenz Julienne <nsaenz@kernel.org>

arch/arm64/boot/dts/broadcom/Makefile

 # SPDX-License-Identifier: GPL-2.0
-dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-4-b.dtb \
+dtb-$(CONFIG_ARCH_BCM2835) += bcm2711-rpi-400.dtb \
+			      bcm2711-rpi-4-b.dtb \
 			      bcm2837-rpi-3-a-plus.dtb \
 			      bcm2837-rpi-3-b.dtb \
 			      bcm2837-rpi-3-b-plus.dtb \

arch/arm64/boot/dts/broadcom/bcm2711-rpi-400.dts

+// SPDX-License-Identifier: GPL-2.0
+#include "arm/bcm2711-rpi-400.dts"