ARM: dts: imx: Add support for DH electronics i.MX8M Plus DHCOM on PDK3

Add support for DH electronics i.MX8M Plus DHCOM SoM on PDK3 carrier board.
Currently supported are serial console, EQoS and FEC ethernets, eMMC, SD,
SPI NOR and USB 3.0 host.

Signed-off-by: Marek Vasut <marex@denx.de>
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index c160e884..a8b55fe 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -996,6 +996,7 @@
 	imx8mq-mnt-reform2.dtb \
 	imx8mq-phanbell.dtb \
 	imx8mp-dhcom-pdk2.dtb \
+	imx8mp-dhcom-pdk3.dtb \
 	imx8mp-evk.dtb \
 	imx8mp-icore-mx8mp-edimm2.2.dtb \
 	imx8mp-msc-sm2s.dtb \