pgsql: Remove duplicate code in brin_memtuple_initialize

Remove duplicate code in brin_memtuple_initialize

Commit 8bf74967dab moved some of the code from brin_new_memtuple to
brin_memtuple_initialize, but this resulted in some of the code being
duplicate. Fix by removing the duplicate lines and backpatch to 10.

Author: Tomas Vondra
Backpatch-through: 10
Discussion: https://postgr.es/m/5eb50c97-9a8e-b691-8c40-1b2a55611c4c%40enterprisedb.com

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/0d0626e27d56a52f78cd71a796ee2e8fe216f217

Modified Files
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src/backend/access/brin/brin_tuple.c | 3 ---
1 file changed, 3 deletions(-)