Merge #16746: msbuild: Ignore linker warning

aff1c9c Adds an option to msbuild common configuration to ignore linker warning 4221. This warning is for object files that do not include any symbols. The warning is harmless and occurs due to some classes that are *nix only having no source to compile for an msvc build. (Aaron Clauson)

Pull request description:

  Adds an option to msbuild common configuration to ignore linker warning 4221. This warning is for object files that do not include any symbols. The warning is harmless and occurs due to some classes that are *nix only having no source to compile for an msvc build.

ACKs for top commit:
  MarcoFalke:
    ACK aff1c9c
  hebasto:
    ACK aff1c9c, I have reviewed the code, it looks OK and I agree it can be merged.
  fanquake:
    ACK aff1c9c

Tree-SHA512: fda3721462d927d8734e16fc0250c7c76b197a085219a9e5267cdd14e19f23f50807d6b5516dee8402b60f3fdf188677e3d618fe6acbdbb5ac3bb635aeb7b297

Author: fanquake

build_msvc/common.init.vcxproj

@@ -113,6 +113,9 @@
       <GenerateDebugInformation>true</GenerateDebugInformation>
       <AdditionalDependencies>crypt32.lib;Iphlpapi.lib;ws2_32.lib;Shlwapi.lib;kernel32.lib;user32.lib;gdi32.lib;winspool.lib;comdlg32.lib;advapi32.lib;shell32.lib;ole32.lib;oleaut32.lib;uuid.lib;odbc32.lib;odbccp32.lib;%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
+    <Lib>
+      <AdditionalOptions>/ignore:4221</AdditionalOptions>
+    </Lib>
   </ItemDefinitionGroup>
   <Import Project="common.init.vcxproj.user" Condition="Exists('common.init.vcxproj.user')" />
 </Project>