[TASK] Use property injection in LanguageController

\TYPO3\CMS\Lang\Controller\LanguageController has 4
inject* Methods which a pretty vanilla and can be replaced
by property injection.

Change-Id: I37181e2bbbd12c9c7fe7b34fe8adafe6f4becec3
Resolves: #44526
Releases: 6.1, 6.0
Reviewed-on: https://review.typo3.org/17722
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn