pgsql: Doc: Fix instructions to control build environment with MSVC

Doc: Fix instructions to control build environment with MSVC

The documentation included some outdated instructions to change the
architecture, build type or target OS of a build done with MSVC.  This
commit updates the documentation to include the modern options
available, down to Visual Studio 2013.

Reported-by: Kyotaro Horiguchi
Author: Juan José Santamaría Flecha
Discussion: https://postgr.es/m/CAC+AXB0J7tAqW_2F1fCE4Dh2=Ccz96TcLpsGXOCvka7VvWG9Qw@mail.gmail.com
Backpatch-through: 12

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/4c95ce048327d465382f265303555ebf32e5dcd0

Modified Files
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doc/src/sgml/install-windows.sgml | 21 +++++++++++++--------
1 file changed, 13 insertions(+), 8 deletions(-)