pgsql: Try to fix MSVC build of pg_rewind.

Try to fix MSVC build of pg_rewind.

It worked in my Windows VM with VS2013, but buildfarm animal mastodon,
running MSVC 2005, was not happy. Amit Kapila also reported a similar error
earlier in his environment. Let's see if this helps.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4babae1a8607ad445cbe761da7f46bb90b156287

Modified Files
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src/tools/msvc/Mkvcbuild.pm |    1 +
1 file changed, 1 insertion(+)