pgsql: Allow negative years in make_date to represent BC years

Allow negative years in make_date to represent BC years

There doesn't seem to be any reason not to allow negative years to be
interpreted as BC, so do that.

The documentation is pretty vague on the details of this function, so
nothing needs to change there.

Reported-by: Andy Abelisto, in bug #14446

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/30bcebbdcf23eb8b78e553c4b3b5eb847410ef19

Modified Files
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src/backend/utils/adt/date.c | 14 +++++++++-----
src/test/regress/expected/date.out | 8 ++++++--
src/test/regress/sql/date.sql | 2 +-
3 files changed, 16 insertions(+), 8 deletions(-)