[BUGFIX] t3lib_softrefproc referenced in DefaultConfiguration

Implementations use makeInstance() / getUserObj() for instantiation,
so it is save to use the new class without file path.

Change-Id: I91562cacf0e828428ff0420bd6bf2302609cb43a
Fixes: #47163
Releases: 6.1
Reviewed-on: https://review.typo3.org/19843
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn
[TASK] Raise submodule pointer

Change-Id: I8117edd90bceb22ba23fd867c888f1429365d319
Reviewed-on: https://review.typo3.org/19846
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn