[SCSI] permit READ DEFECT DATA in block/scsi_ioctl

The soon to be released smartmontools 5.34 uses the
READ DEFECT DATA command on SCSI disks. A disk that
has defect list entries (or worse, an increasing number
of them) is at risk.

Currently the first invocation of smartctl causes this:
   scsi: unknown opcode 0x37
message to appear the console and in the log.

The READ DEFECT DATA SCSI command does not change
the state of a disk. Its opcode (0x37) is valid for
SBC devices (e.g. disks) and SMC-2 devices (media
changers) where it is called INITIALIZE STATUS ELEMENT
WITH RANGE and again doesn't change the external state
of the device.

Changelog:
  - mark SCSI opcode 0x37 (READ DEFECT DATA) as
    safe_for_read
Signed-off-by: NDouglas Gilbert <dougg@torque.net>
Acked-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

drivers/block/scsi_ioctl.c

@@ -123,6 +123,7 @@ static int verify_command(struct file *file, unsigned char *cmd)
 		safe_for_read(READ_12),
 		safe_for_read(READ_16),
 		safe_for_read(READ_BUFFER),
+		safe_for_read(READ_DEFECT_DATA),
 		safe_for_read(READ_LONG),
 		safe_for_read(INQUIRY),
 		safe_for_read(MODE_SENSE),