[BUGFIX] RespectStoragePage does not respect rootLevel

AdditionalWhereClause pid statement for set rootLevel=-1 will be empty,
and for rootLevel = 1 it will limit the query to pid = 0.
For not set rootLevel or rootLevel = 0 the given Pids are taken into
account.

Fixes: #45715
Releases: 6.1
Change-Id: I5f4cdc23273fef186d620e2596a0e3e1eab313ce
Reviewed-on: https://review.typo3.org/18425
Reviewed-by: Frans Saris
Tested-by: Frans Saris
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring