busybox: ensure /storage will be unmounted, dont unmount filesystems we dont need unmount

Signed-off-by: Stephan Raue <stephan@openelec.tv>

packages/sysutils/busybox/init.d/01_mount-filesystem

@@ -38,11 +38,16 @@ case $RUNLEVEL in
 
   poweroff|reboot)
     progress "unmounting filesystems"
-      umount /storage
-      umount /var
-      umount /run
-      umount /dev/shm
-      umount /dev/pts
-      umount /dev
+      for i in 1 2 3 4 5 6 7 8 9 10; do
+        echo "umount /storage"
+        ERR_ENV=1
+        umount /storage
+        [ "$?" -eq "0" ] && ERR_ENV=0 && break
+        usleep 1000000
+      done
+      if [ "$ERR_ENV" -ne "0" ]; then
+        mount -o remount,ro /storage
+        umount -l /storage
+      fi
     ;;
 esac