x86: Support loading kernel setup from a FIT

Add a new setup@ section to the FIT which can be used to provide a setup
binary for booting Linux on x86. This makes it possible to boot x86 from
a FIT.

Signed-off-by: Simon Glass <sjg@chromium.org>

doc/uImage.FIT/kernel.its

@@ -35,3 +35,53 @@
 		};
 	};
 };
+
+
+
+For x86 a setup node is also required: see x86-fit-boot.txt.
+
+/dts-v1/;
+
+/ {
+	description = "Simple image with single Linux kernel on x86";
+	#address-cells = <1>;
+
+	images {
+		kernel@1 {
+			description = "Vanilla Linux kernel";
+			data = /incbin/("./image.bin.lzo");
+			type = "kernel";
+			arch = "x86";
+			os = "linux";
+			compression = "lzo";
+			load = <0x01000000>;
+			entry = <0x00000000>;
+			hash@2 {
+				algo = "sha1";
+			};
+		};
+
+		setup@1 {
+			description = "Linux setup.bin";
+			data = /incbin/("./setup.bin");
+			type = "x86_setup";
+			arch = "x86";
+			os = "linux";
+			compression = "none";
+			load = <0x00090000>;
+			entry = <0x00090000>;
+			hash@2 {
+				algo = "sha1";
+			};
+		};
+	};
+
+	configurations {
+		default = "config@1";
+		config@1 {
+			description = "Boot Linux kernel";
+			kernel = "kernel@1";
+			setup = "setup@1";
+		};
+	};
+};