mount_root will take care of restoring if in the right path

msm89xx/base-files/lib/preinit/79-format-rootfs-data

@@ -11,29 +11,11 @@ has_valid_ext4() {
 	[ "$magic" = "ef53" ]
 }
 
-copy_backup() {
-	local mnt
-
-	mnt=$(mktemp -d)
-	mount -t ext4 "$1" "$mnt" 2>/dev/null || {
-		rmdir "$mnt"
-		return 0
-	}
-
-	if [ -f "$mnt/.overlay-sysupgrade.tgz" ]; then
-		mv "$mnt/.overlay-sysupgrade.tgz" /tmp/sysupgrade.tgz
-	fi
-
-	umount "$mnt"
-	rmdir "$mnt"
-}
-
 preinit_format_rootfs_data() {
 	[ -b "$ROOTFS_DATA" ] || return 0
 	
 	if has_valid_ext4 "$ROOTFS_DATA"; then
 		echo "rootfs_data: valid ext4 filesystem detected" > /dev/kmsg
-		copy_backup "$ROOTFS_DATA"
 		return 0
 	fi