package/systemd: disable portabled

portabled is a container-like service, but so far its still a preview
and basically unknown as the portablectl is hidden in
/usr/lib/systemd.

Disable it for now.

See https://systemd.io/PORTABLE_SERVICES/

Signed-off-by: Norbert Lange <nolange79@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/systemd/systemd.mk

@@ -41,7 +41,8 @@ SYSTEMD_CONF_OPTS += \
 	-Dmount-path=/usr/bin/mount \
 	-Dumount-path=/usr/bin/umount \
 	-Didn=true \
-	-Dnss-systemd=true
+	-Dnss-systemd=true \
+	-Dportabled=false
 
 ifeq ($(BR2_PACKAGE_ACL),y)
 SYSTEMD_DEPENDENCIES += acl