hsm: Distinguish between iface and initiator when creating iSCSI iface

VDSM mistakely assumed that iface name and iface initiator name are the
same, so if admin configured specific initiator name in the host its
value is mistakenly overwritten by ifaceName in the iface file. In such
a case the host fails to establish the iSCSI connection with the target.

Change-Id: I2ea42e63e3e09babaa283c4e97e341ff259a6945
Signed-off-by: Sergey Gotliv <sgotliv@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/25628
Reviewed-by: Nir Soffer <nsoffer@redhat.com>
Reviewed-by: Federico Simoncelli <fsimonce@redhat.com>