I'm a little confused - in your Contents pane, 'Spatial Regulation' is a polygon feature class symbolized by the three unique values -- No-Entry, No-Take, and Take of some attributes, correct? In this case, 'Spatial Regulation' is a feature layer that is symbolized on some attribute.
In order to create the nice legend key, I think you're going to have to export, via the Feature To Line tool, each of the three attributes into separate line feature classes. You'd select all the polygons that have No-Entry and export those polygons to a new line feature class named something like NoEntryLines. Do the same for No-Take to create NoTakeLines, and likewise for Take. Then erase the NoTakeLines. Now use the Merge tool to merge the 3 feature classes back into one line feature class. Add that merged feature class to the map and use it to produce your legend. The issue with this is that the legend will show line geometry, not polygon geometry. If this is a problem, Robert_LeClair's suggestion may be the way to go.