S2IO: Making LED off during LINK_DOWN notification.

- Turning off LED for LINK_DOWN notification
- Return from rxd_owner_bit_reset function if call to set_rxd_buffer_pointer
  fails with ENOMEM

Signed-off-by: Sivakumar Subramani <sivakumar.subramani@neterion.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>