pgsql: Fix meson uuid header check so it works with MSVC

Fix meson uuid header check so it works with MSVC

The OSSP uuid.h file includes unistd.h, so to use it with MSVC we need to
include the postgres include directories so it picks up our version of
that in src/include/port/win32_msvc. Adjust the meson test accordingly.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7c655a04a2dc84b59ed6dce97bd38b79e734ecca

Modified Files
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meson.build | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)