[TASK] Adapt indexes of sys_file_reference

The backend and frontend fire several queries for referenced
files - files with metadata overlay as used in tt_content for
images and media field as well as in pages:media.
Analysing the queries for that some indexed should be added
to improve the query speed on large installations.

This patch adds indexed for the table/fieldname combination
as well es the uid of the record the file is attached to.

Resolves: #54725
Releases: 6.2
Change-Id: I229e27e382e8d0fdaf9bbc0b6729f90dac019e19
Reviewed-on: https://review.typo3.org/26626
Reviewed-by: Steffen Ritter
Tested-by: Steffen Ritter