[BUGFIX] DBAL admin_query() check array before accessing it

Move the $parsedQuery array access after the is_array() check in
DatabaseConnection::admin_query() to avoid PHP warnings.

Releases: master, 6.2
Resolves: #61929
Change-Id: I641d1e0d1dbe0001bd7082fbed1ce5ddb35172f8
Reviewed-on: http://review.typo3.org/33006
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>