pgsql: Fix portability issues with stddev in pg_stat_statements

Fix portability issues with stddev in pg_stat_statements

Stddev is calculated on the fly, and the code in commit 717f70953264 was
using Float8GetDatumFast() inappropriately to convert the result to a
Datum. Mea culpa. It now uses Float8GetDatum().

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/735cd6128a6a401671126443a9af4324932a38d6

Modified Files
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contrib/pg_stat_statements/pg_stat_statements.c |    7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)