pgsql: Fix msvc builds for ActivePerl > 5.24

Fix msvc builds for ActivePerl > 5.24

From this version ActivePerl ships both a .lib and a .a file for the
perl library, which our code would detect as there being no library
available. Instead, we should pick the .lib version and use that.

Report and suggested fix in bug #15065

Author: Heath Lord

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7240962f8626ff09bb8f9e71ecdb074775bdd035

Modified Files
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src/tools/msvc/Mkvcbuild.pm | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)