Windows/DynamicLibrary.inc: Fix trivial warnings. Thanks to John Myers!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134812 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Windows/DynamicLibrary.inc b/lib/Support/Windows/DynamicLibrary.inc
index 4227844..fc5f580 100644
--- a/lib/Support/Windows/DynamicLibrary.inc
+++ b/lib/Support/Windows/DynamicLibrary.inc
@@ -115,7 +115,7 @@
        E = OpenedHandles.end(); I != E; ++I) {
     FARPROC ptr = GetProcAddress((HMODULE)*I, symbolName);
     if (ptr) {
-      return (void *) ptr;
+      return (void *)(intptr_t)ptr;
     }
   }