user32/tests: Drop superfluous function pointer casts.

dlls/user32/tests/dialog.c

@@ -1150,7 +1150,7 @@ static void test_DialogBoxParamA(void)
 static void test_DisabledDialogTest(void)
 {
     g_terminated = FALSE;
-    DialogBoxParam(g_hinst, "IDD_DIALOG", NULL, (DLGPROC)disabled_test_proc, 0);
+    DialogBoxParam(g_hinst, "IDD_DIALOG", NULL, disabled_test_proc, 0);
     ok(FALSE == g_terminated, "dialog with disabled ok button has been terminated\n");
 }
 

dlls/user32/tests/msg.c

@@ -11236,7 +11236,7 @@ static void test_dialog_messages(void)
     cls.lpszClassName = "MyDialogClass";
     cls.hInstance = GetModuleHandle(0);
     /* need a cast since a dlgproc is used as a wndproc */
-    cls.lpfnWndProc = (WNDPROC)test_dlg_proc;
+    cls.lpfnWndProc = test_dlg_proc;
     if (!RegisterClass(&cls)) assert(0);
 
     hdlg = CreateDialogParam(0, "CLASS_TEST_DIALOG_2", 0, test_dlg_proc, 0);