pgsql: Remove overzealous MultiXact freeze assertion.

Remove overzealous MultiXact freeze assertion.

When VACUUM determines that an existing MultiXact should use a freeze
plan that sets xmax to InvalidTransactionId, the original Multi may or
may not be before OldestMxact.  Remove an incorrect assertion that
expected it to always be from before OldestMxact.

Oversight in commit 4ce3af.

Author: Peter Geoghegan <pg@bowt.ie>
Reported-By: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Discussion: https://postgr.es/m/TYAPR01MB5866B24104FD80B5D7E65C3EF5ED9@TYAPR01MB5866.jpnprd01.prod.outlook.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/63c844a0a5d70cdbd6ae0470d582d39e75ad8d66

Modified Files
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src/backend/access/heap/heapam.c | 1 -
1 file changed, 1 deletion(-)