S2IO: Fixes in MSIX related code.

- Calling store_xmsi_data to store the MSI-X datas during initialization
  in s2io-init_nic function
- Disabling NAPI when MSI-X is enabled
- Freeing sp->entries and sp->s2io_entries in s2io_rem_isr

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