ARM: rockchip: Add rv1108-elgin-r1 board support

Add the initial support for Elgin R1 board, which is based on the
RV1108 SoC and has the following features currently supported in
U-Boot:

- UART
- eMMC
- USB

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index 949ee47..dc6f6b2 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -53,6 +53,7 @@
 	rk3399-puma-ddr1600.dtb \
 	rk3399-puma-ddr1866.dtb \
 	rk3399-rock960.dtb \
+	rv1108-elgin-r1.dtb \
 	rv1108-evb.dtb
 dtb-$(CONFIG_ARCH_MESON) += \
 	meson-gxbb-nanopi-k2.dtb \