[TASK] Remove unnecessary require_once statement

The DebugUtility has been required manually for
logDeprecatedFunction() calls before the new Bootstrap
and the new Class Loading mechanism were in place.

This code can now safely be removed.

Resolves: #65946
Releases: master
Change-Id: I55f473c33d457e12109f196e04b8a9046f7531f8
Reviewed-on: http://review.typo3.org/38049


Reviewed-by: Jan Helke <typo3@helke.de>
Tested-by: Jan Helke <typo3@helke.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>