sata_nv: add back some verbosity into ADMA error_handler

Some debug output in the ADMA error_handler function was removed recently,
but it may be useful in certain cases, like NCQ commands timing out. Add it
back in, but make it a bit more intelligent so that it only prints if
command(s) are active and only prints the CPBs for those commands.
That way it won't spew at inappropriate times like suspend/resume.

Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Jeff Garzik <jeff@garzik.org>