pgsql: Add d_type to our Windows dirent emulation.

Add d_type to our Windows dirent emulation.

This allows us to skip some stat calls, by extending commit 861c6e7c to
cover Windows systems.

Author: Juan José Santamaría Flecha <juanjo.santamaria@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Magnus Hagander <magnus@hagander.net>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKG%2BFzxupGGN4GpUdbzZN%2Btn6FQPHo8w0Q%2BAPH5Wz8RG%2Bww%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/87e6ed7c8c6abb6dd62119259d2fd89169a04ac0

Modified Files
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src/include/port/win32_msvc/dirent.h | 11 +++++++++++
src/port/dirent.c                    | 10 ++++++++++
2 files changed, 21 insertions(+)