pgsql: Suppress compiler warning in new jsonb_plperl code.

Suppress compiler warning in new jsonb_plperl code.

Some compilers are evidently pickier than others about whether Perl's
I32 typedef should be considered equivalent to int.  Dodge the problem
by using a separate variable; the prior coding was a bit confusing anyway.

Per buildfarm.  Note this does nothing to fix the test failures due to
SV_to_JsonbValue not covering enough variable types.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d4a4c3d5b433513fc38ce60e454d2c86e8bd0ed4

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