pgsql: Silence compiler warning - Mailing list pgsql-committers

Silence compiler warning

Introduced in de87a084c0a5.

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/563357a12c9b1cdbae29a2d0d09eb9f2c01da4d6

Modified Files
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src/backend/access/heap/heapam.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)