[BUGFIX] Files with unclean path indexed multiple times

When adding a file or requesting a file by an identifier
cleanup any . and .. in the path before handing off
to the driver so files are not indexed multiple times.

Change-Id: I324c4637621165a56470fb95864eeff1254f62dc
Fixes: #46989
Releases: 6.2, 6.1, 6.0
Reviewed-on: https://review.typo3.org/19684
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters