Created attachment 330694 [details] patch to rename libnl-doc-3.2.15 to libnl-doc-3.2.16 emerge fails because libnl-doc-3.2.16.tar.gz actually contains a directory named libnl-doc-3.2.15 (apparently the doc hasn't changed since the last release). renaming the directory during src_prepare fixes the issue.
The patch worked for me.
Thanks for the report and the patch. I slightly reimplemented the patch so it will timebomb on the next careless version bumper. :)