[BUGFIX] Wrong hint in deprecation log for usage of feInterface

Any extension may set parameter $addTofeInterface to 1 in the
corresponding ext_tables.php file.

Assumption that only EXT:statictemplates was setting this parameter
makes it hard to fix faulty third-party extensions.

Releases: master, 6.2
Resolves: #62835
Change-Id: Ib2e75a618eacfb24df8f532f30aa2b55c29597fb
Reviewed-on: http://review.typo3.org/33960
Reviewed-by: Xavier Perseguers <xavier@typo3.org>
Tested-by: Xavier Perseguers <xavier@typo3.org>