Google does not like links generated from widgets and will penalize sites that use them.
However, some widgets add links to a site that a webmaster did not editorially place and contain anchor text that the webmaster does not control. Because these links are not naturally placed, they're considered a violation of Google Webmaster Guidelines.
That widget will do you no good as it is a frame which is not SEO friendly. So the content inside the widget is essentially invisible to the search engines. Additionally, there is no link to your website in that HTML so you're not getting any links from that widget anyway. Basically this is not how you want to make a widget.
<img src="http://example.com/widgets/placeholderimg" width="200" height="200" alt="Map Widget">
<p><a href="http://example.com/">This widget provided by example.com</a></p>