pgsql: Fix incorrect calcSumX2 in numeric deserialize functions

Fix incorrect calcSumX2 in numeric deserialize functions

calcSumX2 is used to inform the aggregate transition function whether it
should include the square of the transition value in the aggregate
state. The deserialize functions for various numeric aggregates that do
use calcSumX2 weren't properly setting the property to true. This does
not matter in core as we never perform any aggregate transitions after a
deserialize operation.

This fix is only required for external code which plumbs aggregate paths
together in such a way that could result in aggregate transitions being
performed after states have been deserialized.

Author: Maxime Schoemans <maxime(dot)schoemans(at)enterprisedb(dot)com>
Reviewed-by: Andrey Borodin <x4mmm(at)yandex-team(dot)ru>
Discussion: https://postgr.es/m/FEBF5C3D-CC53-455F-AA9D-4D377A2E957C@enterprisedb.com
Backpatch-through: 14

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/42ebc601feca2fd5eb065108ec79da12a227d66e

Modified Files
--------------
src/backend/utils/adt/numeric.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)