pgsql: Fix failure of --jobs with reindexdb and vacuumdb on Windows

Fix failure of --jobs with reindexdb and vacuumdb on Windows

FD_SETSIZE needs to be declared before winsock2.h, or it is possible to
run into buffer overflow issues when using --jobs. This is similar to
pgbench's solution done in a23c641.

This has been introduced by 71d84ef, and older versions have been using
the default value of FD_SETSIZE, defined at 64.

Per buildfarm member jacana, but this impacts all Windows animals
running the TAP tests. I have reproduced the failure locally to check
the patch.

Author: Michael Paquier
Reviewed-by: Andrew Dunstan
Discussion: https://postgr.es/m/[email protected]
Backpatch-through: 9.5

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9acda731184c1ebdf99172cbb19d0404b7eebc37

Modified Files
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src/bin/scripts/scripts_parallel.c | 4 ++++
1 file changed, 4 insertions(+)