Adding support for exposing hidden raid components for sg
interface. The sdev->no_uld_attach flag will set set accordingly.

The sas module supports adding/removing raid volumes using online
storage management application interface.

This patch was provided to me by Christoph Hellwig.
Signed-off-by: NEric Moore <Eric.Moore@lsil.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>