dts: arm: socfpga: merge gen5 devicetrees from linux

Add -u-boot.dtsi files to keep the current U-Boot behaviour:
- add u-boot,dm-pre-reloc where required
- disable watchdog
- set uart clock frequency
- add gpio bank-name properties
where appropriate:
- make qspi work (add alias for spi0, fix compatible for flash)
- enable usb (status okay, add alias for udc0)

Adapt board dts files that are not in Linux to keep their old
behaviour.

Change licenses to SPDX.

(Patman warnings/errors are in 1:1 copied files from Linux)

Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
diff --git a/arch/arm/dts/socfpga_cyclone5_sockit-u-boot.dtsi b/arch/arm/dts/socfpga_cyclone5_sockit-u-boot.dtsi
new file mode 100644
index 0000000..648f1bd
--- /dev/null
+++ b/arch/arm/dts/socfpga_cyclone5_sockit-u-boot.dtsi
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * U-Boot additions
+ *
+ * Copyright (C) 2013 Steffen Trumtrar <s.trumtrar@pengutronix.de>
+ * Copyright (c) 2018 Simon Goldschmidt
+ */
+
+/{
+	aliases {
+		spi0 = "/soc/spi@ff705000";
+		udc0 = &usb1;
+	};
+
+	soc {
+		u-boot,dm-pre-reloc;
+	};
+};
+
+&watchdog0 {
+	status = "disabled";
+};
+
+&mmc {
+	u-boot,dm-pre-reloc;
+};
+
+&qspi {
+	u-boot,dm-pre-reloc;
+};
+
+&flash {
+	compatible = "n25q00", "spi-flash";
+	u-boot,dm-pre-reloc;
+};
+
+&uart0 {
+	clock-frequency = <100000000>;
+	u-boot,dm-pre-reloc;
+};
+
+&uart1 {
+	clock-frequency = <100000000>;
+};
+
+&porta {
+	bank-name = "porta";
+};
+
+&portb {
+	bank-name = "portb";
+};
+
+&portc {
+	bank-name = "portc";
+};