[TASK] Clean up ['ctrl'] sortby and default_sortby

sortby: An integer field with an explicit sorting value

default_sortby: A query->orderBy statement to sort records
if no explicit sortby field is given.

default_sortby is ignored if sortby is given. The patch removes
a couple of TCA ['ctrl']['default_sortby'] declarations where both
were defined.

default_sortby needs no "ORDER BY" prefix. The patch removes it
from those TCA tables where this prefix was still defined.

Additionally, the TCA reference docs have been improved in this
area to hint about both fields and their correlation. It is especially
evil if that is confused and a field like 'title' is set as sortby:
The DataHandler would happily write integers into that field on save.

Change-Id: Ib5c38a538cd3f60d3e05033488363a144f756505
Resolves: #80361
Releases: master
Reviewed-on: https://review.typo3.org/52108


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Steffen Kamper <info@sk-typo3.de>
Reviewed-by: Josef Glatz <josef.glatz@typo3.org>
Tested-by: Josef Glatz <josef.glatz@typo3.org>
Tested-by: Mona Muzaffar <mona.muzaffar@gmx.de>
Reviewed-by: Jan Helke <typo3@helke.de>
Tested-by: Jan Helke <typo3@helke.de>
Reviewed-by: Frank Nägler <frank.naegler@typo3.org>
Tested-by: Frank Nägler <frank.naegler@typo3.org>