Having to manually construct the FILES_${PN}-dbg variable is error prone and pretty pointless. We should replace it with some code which simply finds .debug directories and places them into the -dbg package. Yes, its more hardcoded however it means we could remove a ton of pretty boring and useless FILES variables.
Richard has implemented this and Ross did some cleanup, and the patches have now been merged to master: http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=b7766e4bbe61d025346365de4cbafcae56909c27 http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=e0890b662e590d18a4eb7229b469f0078f97b1e7 http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=f1f3716776078d68bd9e3734bca881a486dc2ea3 I'm marking this bug as resolved accordingly.