ARM: dts: stm32: Add DHCOM based PicoITX board

Add DT for DH PicoITX unit, which is a bare-bones carrier board for
the DHCOM. The board has ethernet port, USB, CAN, LEDs and a custom
board-to-board expansion connector.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Patrick Delaunay <patrick.delaunay@st.com>
diff --git a/board/dhelectronics/dh_stm32mp1/u-boot-dhcom.its b/board/dhelectronics/dh_stm32mp1/u-boot-dhcom.its
index 905be57..ba48786 100644
--- a/board/dhelectronics/dh_stm32mp1/u-boot-dhcom.its
+++ b/board/dhelectronics/dh_stm32mp1/u-boot-dhcom.its
@@ -31,6 +31,14 @@
 			arch = "arm";
 			compression = "none";
 		};
+
+		fdt-3 {
+			description = ".dtb";
+			data = /incbin/("arch/arm/dts/stm32mp15xx-dhcom-picoitx.dtb");
+			type = "flat_dt";
+			arch = "arm";
+			compression = "none";
+		};
 	};
 
 	configurations {
@@ -64,6 +72,20 @@
 			fdt = "fdt-2";
 		};
 
+		config-5 {
+			/* DT+SoM+board model */
+			description = "dh,stm32mp15xx-dhcom-picoitx_somrev0_boardrev0";
+			loadables = "uboot";
+			fdt = "fdt-3";
+		};
+
+		config-6 {
+			/* DT+SoM+board model */
+			description = "dh,stm32mp15xx-dhcom-picoitx_somrev1_boardrev0";
+			loadables = "uboot";
+			fdt = "fdt-3";
+		};
+
 		/* Add 587-100..587-400 with fdt-2..fdt-4 here */
 	};
 };