pgsql: Ensure that length argument of memcmp() isn't seen as negative.

Ensure that length argument of memcmp() isn't seen as negative.

I think this will shut up a weird warning from buildfarm member
serinus.  Perhaps it'd be better to change tsCompareString's
length arguments to unsigned, but that seems more invasive
than is justified.

Part of a general push to remove off-the-beaten-track warnings
where we can easily do so.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3b0ee7f583dc347c4aecb57d35830d2f99956e5c

Modified Files
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src/backend/utils/adt/tsvector_op.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)