You can't. Quoting from an ASP.Net forum post:
"The ReportViewer component is not intended to be used with ASP.NET MVC"
You're not the first person to run into this problem. The best advice out there is to add a normal aspx page to the project for the report viewer. You will have to add an ignore route to the application routing.
If you have large amounts of MVC page infrastructure you can add an iframe to an MVC page to host the aspx page with the report viewer.