MSVC: Fix manifest resource encoding

When using the Ninja or Makefile generator with MSVC on Windows
we invoke the resource compiler (`rc.exe`) to compile a manifest
resource.  CMake generates the file with UTF-8 encoding so we
need to add a pragma to inform the resource compiler.

Source/cmcmd.cxx

@@ -1775,6 +1775,8 @@ int cmVSLink::LinkIncremental()
     if (!fout) {
       return -1;
     }
+    // Insert a pragma statement to specify utf-8 encoding.
+    fout << "#pragma code_page(65001)\n";
     fout << this->Type
          << " /* CREATEPROCESS_MANIFEST_RESOURCE_ID */ "
             "24 /* RT_MANIFEST */ \""