[BUGFIX] Prevent fatal when importing a t3d file without fal information

Currently the importer expects that an imported t3d file contains
data for fal. This is not the case if the t3d file comes from
a TYPO3 4.5 installation.

As a result a fatal error is caused because fread is called with
a length of 0.

Resolves: #60540
Releases: 6.3, 6.2
Change-Id: Ib112200c2b6cba0252440cd370d57a6ccd048bf2
Reviewed-on: http://review.typo3.org/31799
Reviewed-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>
Tested-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>