It's optional, drop it. Don't know upstream status of migrating to udev yet.
+*xfburn-0.4.3-r1 (03 May 2010) + + 03 May 2010; Samuli Suominen <ssuominen@gentoo.org> + +xfburn-0.4.3-r1.ebuild: + Remove USE="hal" wrt #313391. Tested with Optiarc DVD RW AD-72000S.