[BUGFIX] Raw search can't search inside the pages table

It's impossible to search the pages table, because a field
definition is wrongly named in the pages TCA.

Fixes: #49242
Releases: 6.2, 6.1, 6.0
Change-Id: I0d1b9eeb4ffdfbff456dfc6249cb23853cb9a357
Reviewed-on: https://review.typo3.org/21502
Reviewed-by: Markus Klein
Tested-by: Markus Klein