fix llvm-lib response file configuration on Windows

Author: owenv

Sources/SWBWindowsPlatform/WindowsLibtool.xcspec

@@ -46,9 +46,15 @@
                 Type = Path;
                 DefaultValue = "llvm-lib.exe";
             },
+            {
+                Name = "LIBTOOL_USE_RESPONSE_FILE";
+                Type = Boolean;
+                DefaultValue = YES;
+            },
             {
                 Name = __INPUT_FILE_LIST_PATH__;
                 Type = Path;
+                Condition = "$(LIBTOOL_USE_RESPONSE_FILE)";
                 // this is set up for us as a read-only property
                 DefaultValue = "$(LINK_FILE_LIST_$(variant)_$(arch))";
                 CommandLineArgs = (