[BUGFIX] Fix typo of variable

$numRows got mixed up with $numrows which could lead to
invalid SQL statements.

Resolves: #63281
Releases: master, 6.2
Change-Id: I209b41d3f502841b74fac7f047aa68a3e45bf271
Reviewed-on: http://review.typo3.org/34532
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>