scsi: core: Rename and move get_scsi_ml_byte()

SCSI has two different getters:

- get_XXX_byte() (in scsi_cmnd.h) which takes a struct scsi_cmnd *, and

- XXX_byte() (in scsi.h) which takes a scmd->result.

The proper name for get_scsi_ml_byte() should thus be without the get_
prefix, as it takes a scmd->result. Rename the function to rectify this.
(This change was suggested by Mike Christie.)

Additionally, move get_scsi_ml_byte() to scsi_priv.h since both scsi_lib.c
and scsi_error.c will need to use this helper in a follow-up patch.

Cc: Mike Christie <[e-mail]>
Reviewed-by: Hannes Reinecke <[e-mail]>
Reviewed-by: Christoph Hellwig <[e-mail]>
Reviewed-by: Bart Van Assche <[e-mail]>
Signed-off-by: Niklas Cassel <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/scsi_lib.c

···
 	return false;
 }
 
-static inline u8 get_scsi_ml_byte(int result)
-{
-	return (result >> 8) & 0xff;
-}
-
 /**
  * scsi_result_to_blk_status - translate a SCSI result code into blk_status_t
  * @result:	scsi error code
···
 	 * Check the scsi-ml byte first in case we converted a host or status
 	 * byte.
 	 */
-	switch (get_scsi_ml_byte(result)) {
+	switch (scsi_ml_byte(result)) {
 	case SCSIML_STAT_OK:
 		break;
 	case SCSIML_STAT_RESV_CONFLICT:

drivers/scsi/scsi_priv.h

···
 	SCSIML_STAT_TGT_FAILURE		= 0x04,	/* Permanent target failure */
 };
 
+static inline u8 scsi_ml_byte(int result)
+{
+	return (result >> 8) & 0xff;
+}
+
 /*
  * Scsi Error Handler Flags
  */