[CLEANUP] Removed unused class WrapperForT3libBeFunc

BackendUtility have to call staticly. The class
WrapperForT3libBeFunc is not used anymore.

Change-Id: I47731e0a6ea33422ba26a418ef87abc302e6135a
Reviewed-on: https://review.typo3.org/31122
Reviewed-by: Jo Hasenau
Tested-by: Jo Hasenau