mips: Add SPL header

Add header with SPL boot mode and type definitions.

Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Marek Vasut <marek.vasut@gmail.com>

arch/mips/include/asm/spl.h

@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2012
+ * Texas Instruments, <www.ti.com>
+ */
+#ifndef	_ASM_SPL_H_
+#define	_ASM_SPL_H_
+
+enum {
+	BOOT_DEVICE_RAM,
+	BOOT_DEVICE_MMC1,
+	BOOT_DEVICE_MMC2,
+	BOOT_DEVICE_MMC2_2,
+	BOOT_DEVICE_NAND,
+	BOOT_DEVICE_ONENAND,
+	BOOT_DEVICE_NOR,
+	BOOT_DEVICE_UART,
+	BOOT_DEVICE_SPI,
+	BOOT_DEVICE_USB,
+	BOOT_DEVICE_SATA,
+	BOOT_DEVICE_I2C,
+	BOOT_DEVICE_BOARD,
+	BOOT_DEVICE_DFU,
+	BOOT_DEVICE_XIP,
+	BOOT_DEVICE_BOOTROM,
+	BOOT_DEVICE_NONE
+};
+
+#ifndef CONFIG_DM
+extern gd_t gdata;
+#endif
+
+#endif