[BUGFIX] Class "\extDirect_DataProvider_BackenduserSettings" not found

A error message is displayed in the Backend. Replace the old class name
with its new name.

Change-Id: Id88b5ff3d315362e7eaf64cc1f33a74b7fd2a84c
Resolves: #52880
Releases: 6.2
Reviewed-on: https://review.typo3.org/24829
Reviewed-by: Markus Klein
Tested-by: Markus Klein
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters