vhost_scsi: module rename

Rename module and update Kconfig and Makefile.
Add alias for compatibility with old userspace
scripts if any.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Asias He <asias@redhat.com>
Acked-by: Nicholas Bellinger <nab@linux-iscsi.org>