ATAPI check condition needs to be treated the same as a success or
protocol return.  The register returns from the PACKET command are all
correctly positioned in the device to host register FIS and so we
should collect them properly.  Right at the moment this doesn't matter
because libata sends a request sense always for ATAPI errors, but if
it ever checked the registers, we should have the correct contents
just in case.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>