scsi: nsp32: drop bus reset

bus reset is a host reset without nsp32hw_init(), and will always return
SUCCESS, thus disabling the use of host reset.  So drop bus reset in
favour of host reset.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>