airoha: pass bootloader device to iopsys_do_upgrade in eMMC case

airoha/base-files/lib/upgrade/platform.sh

@@ -9,7 +9,28 @@ platform_do_upgrade() {
 		return 1
 	fi
 
-	iopsys_do_upgrade "$1" || return
+	local boot_dev=""
+	case "$(get_root_device_type)" in
+	emmc)
+		# search for device-mapper devices with specified name
+		local dir
+		local name='u-boot'
+		for dir in /sys/block/dm-*; do
+			grep -qFx "${name}" "${dir}/dm/name" 2>/dev/null || continue;
+
+			boot_dev=$(grep '^DEVNAME=' "${dir}/uevent" | sed 's|^DEVNAME=|/dev/|')
+			break
+		done
+		if [ -z "${boot_dev}" ]; then
+			log sysupgrade "ERROR: unable to determine boot device."
+			return 1
+		fi
+		;;
+	*)
+		;;
+	esac
+
+	iopsys_do_upgrade "$1" "${boot_dev}" || return
 }
 
 # Tell the bootloader to boot from flash "bank" $1 next time.