class Home(Home):
    @http.route('/web/login', type='http', auth="none")
    def web_login(self, redirect=None, **kw):
        res = super(Home,self).web_login(**kw)
        res.headers.remove('X-Frame-Options')
        return res

Odoo denies x-frame-option in web_login . Just override the method and remove the option will work fine . And additionally needed to remove add_header X-Frame-Options SAMEORIGIN always; in Nginx configuration file