Ticket #48252 - db2index creates index entry from deleted records
Description: Commit ca4d38dff3bd820af2bf60c9bcc82fd64aac2556 fixing
ticket #48252 introduced memory leaks.
. nstombstone_vals needs to be allocated just once and freed at the end.
. when skipping to index an entry for being a tombstone, the entry needs
to be freed.
Reviewed by firstname.lastname@example.org (Thank you, Rich!!)
(cherry picked from commit 4277f2ba4f1bb24efc771ea0fa02354654db255c)