Fix initWithImage on UI7BarButtonItem

I have make some small fix in UI7BarButtonItem

Now Code like below works:

UIImage *leftBarButtonIcon = [UIImage [UIImage imageNamed:@"myImage"]];

UIBarButtonItem *barButtonItem = [[UIBarButtonItem alloc] initWithImage:leftBarButtonIcon
                                                                                                    style:UIBarButtonItemStylePlain
                                                                                                   target:self
                                                                                                   action:@selector(touchLogoutBackButton:)];

self.navigationItem.leftBarButtonItem = barButtonItem;