pgsql: Use correct symbol for minimum int64 value

Use correct symbol for minimum int64 value

The old code used SEQ_MINVALUE to get the smallest int64 value.  This
was done as a convenience to avoid having to deal with INT64_IS_BUSTED,
but that is obsolete now.  Also, it is incorrect because the smallest
int64 value is actually SEQ_MINVALUE-1.  Fix by using PG_INT64_MIN.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/f36ca9af05dd0468cdee28fbdbded690a10ff08b

Modified Files
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contrib/btree_gin/btree_gin.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)