Revert "XWIKI-10021: No public access to main wiki webhome when public access is not allowed on a subwiki."

This reverts commit d52736dda1b160a579968ea8fb1f674de8fe83f4.
XWIKI-10021: No public access to main wiki webhome when public access is not allowed on a subwiki.

* replace $xwiki.checkAccess() by $xwiki.hasAccess()