Bug fix in quasi_topological_sort_nodes(): carefully handle a corner case where 'suc' is reachable both directly from 'src' and via the removed node 'n' - we should not create the edge twice.
Bug fix in quasi_topological_sort_nodes(): carefully handle a corner case where 'suc' is reachable both directly from 'src' and via the removed node 'n' - we should not create the edge twice.

tyb0807/angr,f-prettyland/angr,schieb/angr,tyb0807/angr,axt/angr,f-prettyland/angr,angr/angr,angr/angr,iamahuman/angr,chubbymaggie/angr,chubbymaggie/angr,iamahuman/angr,angr/angr,schieb/angr,axt/angr,tyb0807/angr,f-prettyland/angr,schieb/angr,iamahuman/angr,chubbymaggie/angr,axt/angr