[CLEANUP] Reomve calls to ExtensionManagementUtility::isLoaded(cms)

The sysext cms is always loaded, no need for extra checks

Resolves: #62838
Releases: master
Change-Id: I7812b015516df78837de41fa2b5f1f6f375307f8
Reviewed-on: http://review.typo3.org/33964
Reviewed-by: Frank Nägler <typo3@naegler.net>
Tested-by: Frank Nägler <typo3@naegler.net>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>