dra7x: boot: add dfu bootmode support

This patch enables the DFU boot mode support
for dra7x platform.

Signed-off-by: Ravi Babu <ravibabu@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/common/spl/spl.c b/common/spl/spl.c
index e14ec80..57b73af 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -174,7 +174,7 @@
 # define CONFIG_SPL_LOAD_FIT_ADDRESS	0
 #endif
 
-#ifdef CONFIG_SPL_RAM_DEVICE
+#if defined(CONFIG_SPL_RAM_DEVICE) || defined(CONFIG_SPL_DFU_SUPPORT)
 static ulong spl_ram_load_read(struct spl_load_info *load, ulong sector,
 			       ulong count, void *buf)
 {
@@ -312,6 +312,9 @@
 #ifdef CONFIG_SPL_USB_SUPPORT
 	{ BOOT_DEVICE_USB, "USB" },
 #endif
+#ifdef CONFIG_SPL_DFU_SUPPORT
+	{ BOOT_DEVICE_DFU, "USB DFU" },
+#endif
 #ifdef CONFIG_SPL_SATA_SUPPORT
 	{ BOOT_DEVICE_SATA, "SATA" },
 #endif
@@ -398,6 +401,11 @@
 	case BOOT_DEVICE_USB:
 		return spl_usb_load_image();
 #endif
+#ifdef CONFIG_SPL_DFU_SUPPORT
+	case BOOT_DEVICE_DFU:
+		spl_dfu_cmd(0, "dfu_alt_info_ram", "ram", "0");
+		return spl_ram_load_image();
+#endif
 #ifdef CONFIG_SPL_SATA_SUPPORT
 	case BOOT_DEVICE_SATA:
 		return spl_sata_load_image();