Looks like this version has the same issue as described in bug 237583 (http://bugs.gentoo.org/237583, Comment #3 "The use-flags "dvdarchive liemikuutio" only in combination reproduce this bug"). I got the upgrade installed by now by disabling the USE-flag liemikuutio.
*** Bug 263890 has been marked as a duplicate of this bug. ***
fixed in the tree, moved includes back to dvdnav, dvdread headers need the recent (fixed)libdvdread cvs version. Thanks for reporting this // Also fixed for vdr-1.7.0-r1 with ext-patch-68