scality: add export and name keys to os-initialize_connection info

scality: add export and name keys to os-initialize_connection info

Nova is standardizing on some of the common code for file system type
volume drivers in blueprint consolidate-libvirt-fs-volume-drivers and
expects the 'export' and 'name' keys to be in connection_info['data']
returned from the os-initialize_connection Cinder API.

The Scality volume driver wasn't providing these keys so those are added
here.

Related Nova change: I7db834956c67383e63be2fe2c465118e00273e4b

Closes-Bug: #1475419

Change-Id: I73938c51ac147dca5cf39765768f4ac078bf5e63