arm: mach-k3: sysfw-loader: Add support to load SYSFW from USB

Add support for loading system firmware from a USB mass storage device

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
diff --git a/arch/arm/mach-k3/sysfw-loader.c b/arch/arm/mach-k3/sysfw-loader.c
index 96be069..f4b0d4a 100644
--- a/arch/arm/mach-k3/sysfw-loader.c
+++ b/arch/arm/mach-k3/sysfw-loader.c
@@ -300,6 +300,17 @@
 		ret = k3_sysfw_dfu_download(sysfw_load_address);
 		break;
 #endif
+#if CONFIG_IS_ENABLED(USB_STORAGE)
+	case BOOT_DEVICE_USB:
+		ret = spl_usb_load(&spl_image, &bootdev,
+				   CONFIG_SYS_USB_FAT_BOOT_PARTITION,
+#ifdef CONFIG_K3_SYSFW_IMAGE_NAME
+				   CONFIG_K3_SYSFW_IMAGE_NAME);
+#else
+				   NULL);
+#endif
+#endif
+		break;
 	default:
 		panic("Loading SYSFW image from device %u not supported!\n",
 		      bootdev.boot_device);