[FOLLOWUP][FEATURE] IRRE useCombination option to modify warning text

Fix a fatal and a typo.

Resolves: #64535
Releases: master
Change-Id: I4a04c6482675dbd07771a8e3e2f5659f9360cebe
Reviewed-on: http://review.typo3.org/42314


Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Daniel Goerz <ervaude@gmail.com>
Tested-by: Daniel Goerz <ervaude@gmail.com>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>