Improve logic for making systemd mount dependent on
network-online.target when network filesystem is being used.
This change improves feature implemented in commit [1].
Currently when device is specified by UUID or LABEL, dependency for
network-online.target is added even it's not a network filesystem.
We should be careful with this as it may create circular dependency.
In my case, circular dependency looked like this:
network.target ->
network-pre.target ->
netfilter-persistent.service ->
local-fs.target ->
var-lib-nova.mount ->
network-online.target ->
network.target
Additionally, this commit was originally supposed to add dependency also
for CIFS mounts(these ones starting from '//') but it never worked in my
opinion. It was also fixed by this change.
[1] 6a9dcb6886
Change-Id: I5d2d9c074aa0390a6f8b7c8c0ba1c839fe26f6c5
480bb0c871