Those are generated by links in the page headers.
<link rel="alternate" type="application/rss+xml" title="Recent Changes" href="/feed.php" />
<link rel="alternate" type="application/rss+xml" title="Current Namespace" href="/feed.php?mode=list&ns=" />
This is generated by the function tpl_metaheaders in /inc/template.php:
ptln('<link rel="alternate" type="application/rss+xml" title="Recent Changes" href="'.DOKU_BASE.'feed.php" />',$it);
ptln('<link rel="alternate" type="application/rss+xml" title="Current Namespace" href="'.DOKU_BASE.'feed.php?mode=list&ns='.$INFO['namespace'].'" />',$it);
If you remove those two lines, it should no longer offer the rss feed links.