msxml3: Simplify IXMLDOMNode::removeChild.

dlls/msxml3/node.c

@@ -620,8 +620,6 @@ static HRESULT WINAPI xmlnode_removeChild(
 {
     xmlnode *This = impl_from_IXMLDOMNode( iface );
     xmlNode *child_node_ptr;
-    HRESULT hr;
-    IXMLDOMNode *child;
 
     TRACE("%p->(%p, %p)\n", This, childNode, oldChild);
 
@@ -630,22 +628,15 @@ static HRESULT WINAPI xmlnode_removeChild(
     if(oldChild)
         *oldChild = NULL;
 
-    hr = IXMLDOMNode_QueryInterface(childNode, &IID_IXMLDOMNode, (LPVOID)&child);
-    if(FAILED(hr))
-        return hr;
-
-    child_node_ptr = impl_from_IXMLDOMNode(child)->node;
+    child_node_ptr = impl_from_IXMLDOMNode(childNode)->node;
     if(child_node_ptr->parent != This->node)
     {
         WARN("childNode %p is not a child of %p\n", childNode, iface);
-        IXMLDOMNode_Release(child);
         return E_INVALIDARG;
     }
 
     xmlUnlinkNode(child_node_ptr);
 
-    IXMLDOMNode_Release(child);
-
     if(oldChild)
     {
         IXMLDOMNode_AddRef(childNode);