CMS a content management system so it is mainly aimed at helping the administrator of the site to add new content, update links, better SEO etc. It also enforces the developer to develope in a certain way (use some CMS predefined functions, structure data in a certain way).
MVC framework are meant to help developers develop in a more robust way and giving the developer tools for easier development like: structured URLs (MVC), helper functions etc.
So to summarize:
- CMS - helps during development but mainly helps manage the site
- MVN FW - helps to develop the site