pgsql: meson: Define HAVE_LOCALE_T for msvc

meson: Define HAVE_LOCALE_T for msvc

Meson doesn't see the redefinition of locale_t done in
src/include/port/win32_port.h, so it is not defining HAVE_LOCALE_T,
HAVE_WCSTOMBS_L nor HAVE_MBSTOWCS_L as the current
src/tools/msvc/build.pl script does.  Add manual overrides to fix.

Author: Author: Juan Jose Santamaria Flecha <juanjo.santamaria@gmail.com>
Discussion:
https://www.postgresql.org/message-id/flat/CAC%2BAXB1wJEqfKCuVcNpoH%3Dgxd61N%3D7c2fR3Ew6YRPpSfEUA%3DyQ%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/373679c4a82f04e6c16198cdffab1a6c56852956

Modified Files
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meson.build | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)