wickedd fails to start if local mount is nested over nfs mount

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Environment

SUSE Linux Enterprise Server 12 Service Pack 1 (SLES 12 SP1)
SUSE Linux Enterprise Server 12

Situation

When a local fs or device is mounted over a NFS mount, nscd and wickedd and subsequently network fail to start during boot.
For example /etc/fstab would look like this:

/dev/system/root        /               ext4    acl,user_xattr    1 1
nfs-server:/nfsmount 	/mnt-test       nfs	defaults          0 0
/dev/mapper/<dev-name>  /mnt-test/data  ext4    defaults          0 0

In this case, the local /dev/mapper/dev is mounted over the nfs mount: /nfsmount.
The following is logged in the boot messages:

systemd[1]: Breaking ordering cycle by deleting job wickedd-nanny.service/start
systemd[1]: Job wickedd-nanny.service/start deleted to break ordering cycle starting with wicked.service/start
systemd[1]: Found ordering cycle on wicked.service/start
systemd[1]: Found dependency on wickedd.service/start
systemd[1]: Found dependency on local-fs.target/start
systemd[1]: Found dependency on mnt-test.mount/start
systemd[1]: Found dependency on mnt.mount/start
systemd[1]: Found dependency on network-online.target/start
systemd[1]: Found dependency on wicked.service/start
systemd[1]: Breaking ordering cycle by deleting job wickedd.service/start

Resolution

Adding the mount option _netdev to the local mount fixes the ordering cycle, as an example, the line in /etc/fstab will look like this after:

/dev/mapper/<dev-name>  /mnt-test/data  ext4    defaults,_netdev     0 0

Cause

The local fs has to come up first and then the network filesystem.
Now in this case the local fs (/dev/mapper) counts as filesystem based on network as well because it's mount point is on a network filesystem. However it's recognized as local fs and wickedd is tried to be started too early.

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