pgsql: Honor MSVC WindowsSDKVersion if set

Honor MSVC WindowsSDKVersion if set

Add a line to the project file setting the target SDK. Otherwise, in for
example VS2017, if the default but optional 8.1 SDK is not installed the
build will fail.

Patch from Peifeng Qiu, slightly edited by me.

Discussion: /messages/by-id/CABmtVJhw1boP_bd4=b3Qv5YnqEdL696NtHFi2ruiyQ6mFHkeQQ@mail.gmail.com

Backpatch to all live branches.

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/fe9e632846a1888b93699d08c7513b35fcce63fb

Modified Files
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src/tools/msvc/MSBuildProject.pm | 13 +++++++++++++
1 file changed, 13 insertions(+)