[BUGFIX] Menu-links generate two empty spaces at closing anchor

Checks for ATagParams & access key code before adding empty
spaces between anchor parameters.

Resolves: #50566
Releases: 6.3, 6.2, 6.1
Change-Id: I57a2a2a06a97fc1eda6e0438bfdc6e210437e5bb
Reviewed-on: http://review.typo3.org/31682
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>