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: https://postgr.es/m/CABmtVJhw1boP_bd4=b3Qv5YnqEdL696NtHFi2ruiyQ6mFHkeQQ@mail.gmail.com

Backpatch to all live branches.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/20e99cdddbd3b55257827d621c2f9c592521cd4b

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