unable to find ftd1_doc.i (slackware current)

Hi, I've just upgraded to the latest version of Slackware current and I can't build libftdi1 using sbopkg and Ponce's repository for current. I get the error message 'unable to find ftd1_doc.i'. Supposedly this is related to compiling in parallel and DOXGEN. Two suggestions to fix this that I've found are to disable the parallelism or disabling the generation of the documentation. I don't know how to do either of these. Any help/suggestions is greatly appreciated. Thanks.