ncr5380: Use return instead of goto in NCR5380_select()

The "failed" label in NCR5380_select() is not helpful. Some failures
return 0, others -1. Use return instead of goto to improve clarity and
brevity, like atari_NCR5380.c does. Fix the relevant comments.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>