fix(dmsquash-live): use the overlay size with thin provisioning

Using the overlay size in the device mapper table allows the filesystem
in the base image to be extended if the overlay is larger than the
base image (e.g. `resize2fs /dev/mapper/live-rw`).

modules.d/90dmsquash-live/dmsquash-live-root.sh

@@ -298,7 +298,7 @@ do_live_overlay() {
         dmsetup message /dev/mapper/live-overlay-pool 0 "create_thin 0"
 
         # Create a snapshot of the base image
-        echo 0 "$sz" thin /dev/mapper/live-overlay-pool 0 "$base" | dmsetup create live-rw
+        echo 0 "$thin_data_sz" thin /dev/mapper/live-overlay-pool 0 "$base" | dmsetup create live-rw
     elif [ -z "$overlayfs" ]; then
         echo 0 "$sz" snapshot "$base" "$over" PO 8 | dmsetup create live-rw
     fi