pgsql: Silence "missing contrecord" error.

Silence "missing contrecord" error.

Commit dd38ff28ad added a new error message "missing contrecord" when
we fail to reassemble a record.  Unfortunately that caused noisy
messages to be logged by pg_waldump at end of segment, and by walsender
when asked to shut down on a segment boundary.

Remove the new error message, so that this condition signals end-of-
WAL without a message.  It's arguably a reportable condition that should
not be silenced while performing crash recovery, but fixing that without
introducing noise in the other cases will require more research.

Back-patch to 15.

Reported-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Discussion: https://postgr.es/m/6a1df56e-4656-b3ce-4b7a-a9cb41df8189%40enterprisedb.com

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/76d5966b3b798cc58025c77164fa944f2b6dd667

Modified Files
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src/backend/access/transam/xlogreader.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)