Add overlay initial support (#23)

* Add overlay initial support

* Create load

* Cleanup NL

* Reorg dts files

* Update update-dtb.sh

buildroot-external/fdt/barebox-state-efi.dts

@@ -0,0 +1,67 @@
+/dts-v1/;
+/ {
+
+	aliases {
+		state = &state;
+	};
+
+	state: state {
+		#address-cells = <1>;
+		#size-cells = <1>;
+                magic = <0xef98423f>;
+                compatible = "barebox,state";
+                backend = <&backend_state>;
+                backend-type = "raw";
+                backend-stridesize = <4048>;
+
+		bootstate {
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			system0 {
+				#address-cells = <1>;
+				#size-cells = <1>;
+				remaining_attempts@0 {
+					reg = <0x0 0x4>;
+					type = "uint32";
+					default = <3>;
+				};
+				priority@4 {
+					reg = <0x4 0x4>;
+					type = "uint32";
+					default = <20>;
+				};
+			};
+			system1 {
+				#address-cells = <1>;
+				#size-cells = <1>;
+				remaining_attempts@8 {
+					reg = <0x8 0x4>;
+					type = "uint32";
+					default = <0>;
+				};
+				priority@c {
+					reg = <0xc 0x4>;
+					type = "uint32";
+					default = <10>;
+				};
+			};
+			last_chosen@10 {
+				reg = <0x10 0x4>;
+				type = "uint32";
+			};
+		};
+	};
+
+	partitions {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "fixed-partitions";
+
+		backend_state: state {
+			partuuid = "33236519-7f32-4dff-8002-3390b62c309d";
+		};
+	};
+
+};
+