[BUGFIX] Select icon added via pageTsConfig not shown

Fix for issue #78628 fixed "addItems" for TCA trees, but broke them
for select drop downs. Juggle icon providing around a bit to fix.

Change-Id: I3a1077992a7db0d72bc2d7d0247292763cc25958
Resolves: #78747
Related: #78628
Releases: master
Reviewed-on: https://review.typo3.org/51766


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Mona Muzaffar <mona.muzaffar@gmx.de>
Tested-by: Mona Muzaffar <mona.muzaffar@gmx.de>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>