[TASK] Add calls to sql_free_result in ajax calls

Change-Id: Ied54ed7fed0ac0b9432603a204ee190ba99d965f
Resolves: #62297
Reviewed-on: http://review.typo3.org/33348
Reviewed-by: Sebastian Fischer <typo3@evoweb.de>
Tested-by: Sebastian Fischer <typo3@evoweb.de>