pgsql: Remove hastup from LVPagePruneState.

Remove hastup from LVPagePruneState.

Instead, just have lazy_scan_prune() and lazy_scan_noprune() update
LVRelState->nonempty_pages directly. This makes the two functions
more similar and also removes makes lazy_scan_noprune need one fewer
output parameters.

Melanie Plageman, reviewed by Andres Freund, Michael Paquier, and me

Discussion: http://postgr.es/m/CAAKRu_btji_wQdg=ok-5E4v_bGVxKYnnFFe7RA6Frc1EcOwtSg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e2d5b3b9b643739bd83e42769b44005dfd2bbb90

Modified Files
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src/backend/access/heap/vacuumlazy.c | 53 +++++++++++++++++++-----------------
1 file changed, 28 insertions(+), 25 deletions(-)