Merge bitcoin/bitcoin#22230: build: Fix MSVC linker /SubSystem option for bitcoin-qt.exe

9edd713 build: Fix MSVC linker /SubSystem option for bitcoin-qt.exe (Hennadii Stepanov)

Pull request description:

  On master (6f3fbc0), running `bitcoin-qt.exe`, which was built with MSVC, causes a terminal window open along with the GUI.

  This PR fixes such behavior. See Microsoft [docs](https://docs.microsoft.com/en-us/cpp/build/reference/subsystem-specify-subsystem?view=msvc-160).

  It is still possible to use the `-printtoconsole` option for debug builds.

ACKs for top commit:
  sipsorcery:
    tACK 9edd713.

Tree-SHA512: 02f2874b13e484f98344f6a7e3b01fa82a78a39865787c77bd674ead22a84a7f98a1849ccad26bd2b8c8603b3e29dcc1633b0ad731ce7d61be2d6b1f9584839c

Author: fanquake

build_msvc/bitcoin-qt/bitcoin-qt.vcxproj

@@ -55,6 +55,7 @@
       <AdditionalIncludeDirectories>$(QtIncludes);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>
     <Link>
+      <SubSystem>Windows</SubSystem>
       <AdditionalDependencies>$(QtReleaseLibraries);%(AdditionalDependencies)</AdditionalDependencies>
       <AdditionalOptions>/ignore:4206 /LTCG:OFF</AdditionalOptions>
     </Link>