Run volatile media before mdev

Without volatile media mountpoints under media are not populated,
so mounts defined on fstab are failing to mount by mdev at fstab
location. Later at boot volatile media run again followed by mdev
and now mount fstab succeds, so you have same device mounted twice

Running volatile media before mdev fixes above issue.
Merge pull request #7 from athoik/volatile

Run volatile media before mdev
Merge remote-tracking branch 'oe/master'

* oe/master:
  Run volatile media before mdev