Revert "[BUGFIX] Fix wrong column title in web>list for field colpos"

This reverts commit cd412c715b9947e18bd8cecf6eea83cc04bb9479

The patch triggers warnings and errors in multiple extensions. Digging
into the details shows the implementation is neither finished nor
stable. See issue #25113 for a detailed analysis.

Change-Id: Iafc11e0c4bc9ef99329c33ce1bebc289d9836512
Related: #25113
Fixes: #45833
Releases: 6.1, 6.0, 4.7, 4.6, 4.5
Reviewed-on: https://review.typo3.org/18944
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn