pgsql: Make lazy_vacuum_heap_rel match lazy_scan_heap.

Make lazy_vacuum_heap_rel match lazy_scan_heap.

Make lazy_vacuum_heap_rel variable names match those from lazy_scan_heap
where that makes sense.

Extracted from a larger patch to deal with issues with how vacuumlazy.c
sets pages all-frozen.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: /messages/by-id/CAH2-WznuNGSzF8v6OsgjaC5aYsb3cZ6HW6MLm30X0d65cmSH6A@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d30b499997caa77805c112b3e0524d2bca8f3e48

Modified Files
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src/backend/access/heap/vacuumlazy.c | 24 ++++++++----------------
1 file changed, 8 insertions(+), 16 deletions(-)