Do not use static boost runtime (facebook#792)

Summary:
Pull Request resolved: facebook#792

As title. This seems no longer supported. The binary still looks mostly-static (just regular MS dlls).

Reviewed By: wsanville

Differential Revision: D46959547

fbshipit-source-id: d240d1dd227632d33746ed0d8133877cf7837d79

cmake_modules/Commons.cmake

@@ -41,7 +41,7 @@ macro(add_dependent_packages_for_redex)
 
     if(ENABLE_STATIC)
         set(Boost_USE_STATIC_LIBS ON)
-        if(NOT APPLE)
+        if((NOT APPLE) AND (NOT MINGW))
             set(Boost_USE_STATIC_RUNTIME ON)
         endif()
         set(Boost_USE_MULTITHREADED ON)