Description of problem:
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While creating gluster data domain, when checking the option 'use managed gluster volume', lists the set of all gluster volumes in the cluster, irrespective of the state of the volume (i.e) started or stopped.

It would make sense only to list the set of all volumes that are in started state

Version-Release number of selected component (if applicable):
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ovirt-4.1.0.4

How reproducible:
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Always

Steps to Reproduce:
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1. Create a hyperconverged cluster ( both virt and gluster service enabled )
2. Manage the gluster replica 3, sharded volume in that cluster. Leave it in created state and never start the volume. ( volume is in created state and its DOWN )
3. Create a Gluster data domain by selecting 'Use Managed Gluster Volume'
4. Select the volume mount as listed

Actual results:
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The volume which is down ( just created and not started ) is being listed when associating gluster data domain to gluster volume.

Expected results:
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Only the volumes which are in the started stated should be listed when associating the gluster data domain to gluster volume