pgsql: pg_buffercache: Remove unused fields from BufferCacheNumaRec

pg_buffercache: Remove unused fields from BufferCacheNumaRec

These fields have been added in commit ba2a3c2302f, and have never been
used. While on it, this commit moves a comment that was out of place,
improving it.

Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: /messages/by-id/aSBOKX6pLJzumbmF@ip-10-97-1-34.eu-west-3.compute.internal

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7d9043aee803bf9bf3307ce5f45f3464ea288cb1

Modified Files
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contrib/pg_buffercache/pg_buffercache_pages.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)