pgsql: Fix jsonb_plperl to convert Perl UV values correctly.

Fix jsonb_plperl to convert Perl UV values correctly.

Values greater than IV_MAX were incorrectly converted to SQL,
for instance ~0 would become -1 rather than 18446744073709551615
(on a 64-bit machine).

Dagfinn Ilmari Mannsåker, adjusted a bit by me

Discussion: https://postgr.es/m/d8jtvskjzzs.fsf@dalvik.ping.uio.no

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/93b6e03ab4794272986a11a427c6c391eafa5dea

Modified Files
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contrib/jsonb_plperl/expected/jsonb_plperl.out  | 16 +++++++++++++++-
contrib/jsonb_plperl/expected/jsonb_plperlu.out | 16 +++++++++++++++-
contrib/jsonb_plperl/jsonb_plperl.c             | 19 ++++++++++++++++++-
contrib/jsonb_plperl/sql/jsonb_plperl.sql       | 12 ++++++++++++
contrib/jsonb_plperl/sql/jsonb_plperlu.sql      | 12 ++++++++++++
5 files changed, 72 insertions(+), 3 deletions(-)