GlusterFS: set correct filename when cloning volume

When cloning a volume, the volume[name] field was populated
with incorrect data, resulting in an unexpected filename containing
the volume data.  This results in failures of later operations on
that cloned volume.

Change-Id: I067ed44cebdc8e91e9ded326953fd0c99d003f05
Closes-Bug: #1244238
Merge "GlusterFS: set correct filename when cloning volume"