build-sys,visual studio: Add x64 build support

[ArcsinX]

This patch adds ability to build ctags using Visual Studio project from x64 native shell

[codecov]

Codecov Report

Merging #2956 (2381ebd) into master (23870d6) will not change coverage.
The diff coverage is n/a.

❗ Current head 2381ebd differs from pull request most recent head ccaacfe. Consider uploading reports for the commit ccaacfe to get more accurate results

@@           Coverage Diff           @@
##           master    #2956   +/-   ##
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  Coverage   87.24%   87.24%           
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  Files         194      194           
  Lines       44426    44426           
=======================================
  Hits        38760    38760           
  Misses       5666     5666           

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[k-takata]

I haven't tested this on my local environment, but the changes look good.
Let's merge this and see what's happen.