pgsql: Remove pointless HeapTupleHeaderIndicatesMovedPartitions calls

Remove pointless HeapTupleHeaderIndicatesMovedPartitions calls

Pavan Deolasee recently noted that a few of the
HeapTupleHeaderIndicatesMovedPartitions calls added by commit
5db6df0c0117 are useless, since they are done after comparing t_self
with t_ctid. But because t_self can never be set to the magical values
that indicate that the tuple moved partition, this can never succeed: if
the first test fails (so we know t_self equals t_ctid), necessarily the
second test will also fail.

So these checks can be removed and no harm is done. There's no bug
here, just a code legibility issue.

Reported-by: Pavan Deolasee <pavan(dot)deolasee(at)gmail(dot)com>
Discussion: https://postgr.es/m/20200929164411.GA15497@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0f5505a8815aa4eb03ca61245a5a51ff9adda2f4

Modified Files
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src/backend/access/heap/heapam.c | 12 ++++--------
src/backend/access/heap/heapam_visibility.c | 9 +++------
2 files changed, 7 insertions(+), 14 deletions(-)