sata_mv: group genIIe flags

Group all of the flags for GenIIe devices into a common definition,
to ensure that any updates to them are shared by all GenIIe devices.

This will help make future maintenance somewhat simpler.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>