pgsql: Silence compiler warning in assertion-enabled builds.

Silence compiler warning in assertion-enabled builds.

With -Wtype-limits, gcc correctly points out that size_t can never be < 0.
Backpatch to 9.3 and 9.2. It's been like this forever, but in <= 9.1 you got
a lot other warnings with -Wtype-limits anyway (at least with my version of
gcc).

Andres Freund

Branch
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REL9_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/ae8fc624066398b8a14a97c5f950ddc844657d24

Modified Files
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src/pl/plpython/plpy_procedure.c |    4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)