airoha: sysupgrade: Pass image name to copy_config

This allows getting an offset of new fitblk overlay from upgrade image.

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

@@ -55,8 +55,9 @@ platform_get_bootbank() {
 }
 
 platform_copy_config() {
+	local image="$1"
 	log "Copy config files"
-	iopsys_copy_config
+	iopsys_copy_config "$image"
 }
 
 __get_bootloader_device() {