[TASK] Followup: Get rid of old classnames like t3lib_...

Never use "use"-statements in ext_localconf.php!
That will lead to problems when files are merged.
Followup to change-id I4e7d41936b85c76c73dce504ffc51a412a1a5429

Change-Id: I0a0be7a17db0f299be1b65097dd709ee1df87b28
Resolves: #60584
Releases: master
Reviewed-on: http://review.typo3.org/34835
Reviewed-by: Benjamin Mack <benni@typo3.org>
Tested-by: Benjamin Mack <benni@typo3.org>