Yes, I was meaning Goggle sitemap.xml, sorry for the confusion. On Kentico MVC I'm not aware of any out-of-the-box functionality to generate Sitemap XML automatically. I can see, that this SEO URL settings support article contains the mention of Google Sitemap, but there is also a small note:
This page must contain the Google Sitemap (XML Sitemap) web part. If left empty, a full sitemap of the website is automatically generated by the ~/CMSPages/GoogleSiteMap.aspx system page.
As far as I know these things (web parts and /CMSPages) exist only on Portal Engine. So my best guess (I'm not 100% certain) would be it's just an error in the documentation and these setting should have been removed from MVC article and left for Portal Engine only. The fact these sitemap settings don't exist (they are just hidden, but still there in the database) in Kentico CMS admin for MVC page types is another proof of it. Therefore Google Sitemap on MVC should be implemented as a custom build. You can confirm this with Kentico support I think to be 100% sure.