lip_hook: check existence of initrd_hook directory

contrib/initrd/initrd_hook/24liphook

@@ -27,11 +27,15 @@ log_begin_msg "$DESCRIPTION"
 #cp /lip/no-bootloader-icon/ubiquity-kdeui-no-bootloader.desktop /root/usr/share/applications/kde4/
 
 #TODO: install ubiquity here?
+if [ -d "${LIP_HOOKS}" ]; then
   for hook in $(find "${LIP_HOOKS}" -name "*.hook.sh"); do
     log_begin_msg "Executing lip hook ${hook}"
     /bin/sh "${hook}"
     log_end_msg
   done
+else
+  log_warning_msg "No lip hook directory avaiable in /cdrom"
+fi
 
 log_end_msg