rockchip: rk3568: Add support for FriendlyARM NanoPi R5C

FriendlyARM NanoPi R5C is an open-sourced mini IoT gateway device.

Specification:
- Rockchip RK3568
- 1/4GB LPDDR4X RAM
- 8/32GB eMMC
- SD card slot
- M.2 Connector
- 2x USB 3.0 Port
- 2x 2500 Base-T (PCIe, r8125)
- HDMI 2.0
- MIPI DSI/CSI
- USB Type C 5V

The device tree is taken from kernel v6.4-rc1.

Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Signed-off-by: Tianling Shen <cnsztl@gmail.com>
diff --git a/arch/arm/dts/rk3568-nanopi-r5c-u-boot.dtsi b/arch/arm/dts/rk3568-nanopi-r5c-u-boot.dtsi
new file mode 100644
index 0000000..fe5bc6a
--- /dev/null
+++ b/arch/arm/dts/rk3568-nanopi-r5c-u-boot.dtsi
@@ -0,0 +1,3 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+
+#include "rk3568-nanopi-r5s-u-boot.dtsi"