webadmin: select GlusterFS storage type in New Storage Domain

In a GlusterFS Data Center, when creating a second
storage domain, GlusterFS Storage type is not selected
by default.
This is fixed now.

Change-Id: Id32c2c11da506da073bde9bed0328d408bd9e53e
Bug-Url: https://bugzilla.redhat.com/1005832
Signed-off-by: Kanagaraj M <kmayilsa@redhat.com>