pgsql: vacuumlazy.c: Further consolidate resource allocation.

vacuumlazy.c: Further consolidate resource allocation.

Move remaining VACUUM resource allocation and deallocation code from
lazy_scan_heap() to its caller, heap_vacuum_rel().  This finishes off
work started by commit 73f6ec3d.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wzk3fNBa_S3Ngi+16GQiyJ=AmUu3oUY99syMDTMRxitfyQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c42a6fc41dc22b42e5417224440c02893996afb4

Modified Files
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src/backend/access/heap/vacuumlazy.c | 72 +++++++++++++++---------------------
1 file changed, 30 insertions(+), 42 deletions(-)