Reverting small project file change that snuck in.

gameplay/gameplay.vcxproj

@@ -1026,7 +1026,6 @@
       <AdditionalIncludeDirectories>$(ProjectDir)src;..\external-deps\lua\include;..\external-deps\bullet\include;..\external-deps\openal\include\AL;..\external-deps\alut\include\AL;..\external-deps\oggvorbis\include;..\external-deps\glew\include;..\external-deps\libpng\include;..\external-deps\zlib\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DebugInformationFormat>
       </DebugInformationFormat>
-      <AdditionalOptions>/MP %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
       <SubSystem>Windows</SubSystem>