portmap: fix FILESEXTRAPATHS

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

meta-systemd/oe-core/recipes-connectivity/portmap/portmap_6.0.bbappend

@@ -1,4 +1,4 @@
-FILESEXTRAPATHS := "${THISDIR}/${PN}"
+FILESEXTRAPATHS_prepend := "${THISDIR}/${BPN}:"
 
 inherit systemd
 
@@ -9,8 +9,8 @@ SYSTEMD_SERVICE_${PN} = "portmap.service"
 SYSTEMD_AUTO_ENABLE = "disable"
 
 SRC_URI_append = " file://portmap.service"
+
 do_install_append() {
     install -d ${D}${systemd_unitdir}/system
     install -m 0644 ${WORKDIR}/portmap.service ${D}${systemd_unitdir}/system
 }
-