[BUGFIX] Fix autoloader_smartobject example

Add the default label, if there is no LLL key in the
translation handling.

Resolves: #60812
Related: #60811
Change-Id: I90e3f6a0859c0fb4acf759155f0425341327cecc
Reviewed-on: http://review.typo3.org/32022
Reviewed-by: Tim Lochmüller <tim@fruit-lab.de>
Tested-by: Tim Lochmüller <tim@fruit-lab.de>