[libata] PM code cleanup for ata port

[libata] PM code cleanup for ata port

For system freeze, if the port is already runtime suspended, leave it
alone and just return. The port will be resumed on thaw before it will
be used.

And since we will call get_noresume for every device during prepare
phase, and the port is resumed during thaw phase, it can't be in runtime
suspended state during the poweroff phase. So remove the
runtime_suspended check in poweroff callback.

And for all suspend(freeze/suspend/poweroff/etc.), there is no need to
touch the device, so set no_autopsy and no_recovery for them all.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>