pgsql: Remove LVPagePruneState.

Remove LVPagePruneState.

Commit cb970240f13df2b63f0410f81f452179a2b78d6f moved some code from
lazy_scan_heap() to lazy_scan_prune(), and now some things that used to
need to be passed back and forth are completely local to lazy_scan_prune().
Hence, this struct is mostly obsolete. The only thing that still
needs to be passed back to the caller is has_lpdead_items, and that's
also passed back by lazy_scan_noprune(), so do it the same way in both
cases.

Melanie Plageman, reviewed and slightly revised by me.

Discussion: http://postgr.es/m/CAAKRu_aM=OL85AOr-80wBsCr=vLVzhnaavqkVPRkFBtD0zsuLQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e313a611370410f4efe4e816767759870b69dfa6

Modified Files
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src/backend/access/heap/vacuumlazy.c | 135 ++++++++++++++++++-----------------
src/tools/pgindent/typedefs.list | 1 -
2 files changed, 69 insertions(+), 67 deletions(-)