[TASK] Superfluous comparison in Language

Fix superfluous comparison against boolean in
Laguage::getLanguages

Change-Id: Idbf4c1f234eb1c60c01ea130095759ef49ce71c0
Resolves: #54054
Releases: 6.2
Reviewed-on: https://review.typo3.org/25741
Reviewed-by: Xavier Perseguers
Reviewed-by: Michiel Roos
Tested-by: Michiel Roos
Reviewed-by: Markus Klein
Tested-by: Markus Klein