[BUGFIX] Dummy WHERE condition compatibility

The Typo3DbBackend.php places a dummy where condition in case
$statementParts['where'] is empty. The condition is changed
for compatibility reasons with some DBMS.

Resolves: #61639
Releases: 6.3, 6.2
Change-Id: If3f23af43fea6460407e8b05f9bcd782c6e08f0d
Reviewed-on: http://review.typo3.org/32804
Reviewed-by: Markus Klein <klein.t3@reelworx.at>
Tested-by: Markus Klein <klein.t3@reelworx.at>