dxtrans: Add DllGetClassObject stub.

dlls/dxtrans/Makefile.in

 MODULE    = dxtrans.dll
+
+C_SRCS = \
+	main.c

dlls/dxtrans/dxtrans.spec

@@ -6,6 +6,6 @@
 @ stub ?DXOverArrayMMX@@YGXPAVDXPMSAMPLE@@PBV1@K@Z
 @ stdcall -private DllCanUnloadNow()
 @ stub DllEnumClassObjects
-@ stub DllGetClassObject
+@ stdcall -private DllGetClassObject(ptr ptr ptr)
 @ stdcall -private DllRegisterServer()
 @ stdcall -private DllUnregisterServer()

dlls/dxtrans/main.c

+/*
+ * DirectX Transitions
+ *
+ * Copyright 2021 Alex Henrie
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#include <stdarg.h>
+
+#define COBJMACROS
+
+#include "windef.h"
+#include "winbase.h"
+#include "wine/debug.h"
+
+WINE_DEFAULT_DEBUG_CHANNEL(dxtrans);
+
+HRESULT WINAPI DllGetClassObject(REFCLSID clsid, REFIID riid, void **out)
+{
+    FIXME("(%s, %s, %p) stub!\n", debugstr_guid(clsid), debugstr_guid(riid), out);
+    return CLASS_E_CLASSNOTAVAILABLE;
+}