pgsql: Fix setvbuf()-induced crash in libpq_pipeline

Fix setvbuf()-induced crash in libpq_pipeline

Windows doesn't like setvbuf(..., _IOLBF) and crashes if you use it,
which has been causing the libpq_pipeline failures all along ... and our
own port.h has known about it for a long time: it offers PG_IOLBF that's
defined to _IONBF on that platform. Follow its advice.

While at it, get rid of a bogus bitshift that used a constant of the
wrong size. Decorate the constant as LL to fix. While at it, remove a
pointless addition that only confused matters.

All as diagnosed by Tom Lane.

Discussion: https://postgr.es/m/3458958.1617302154@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a68a894f0198aaeffa81b3027f135adcdaa8abf6

Modified Files
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src/test/modules/libpq_pipeline/libpq_pipeline.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)