Staging: comedi: replace pr_err with dev_err

This patch replace pr_err with dev_err, when appropriate device
structure is found.
Issue found using the following Coccinelle script:

@r exists@
identifier f, s, i;
position p;
@@

f(...,struct s *i,...) {
<+...
when != i == NULL
pr_err@p(...);
...+>
}

@rr@
identifier r.s, fld;
@@

struct s {
	...
	struct device *fld;
	...
};

@@
identifier r.i, rr.fld;
position r.p;
@@
-pr_err@p
+dev_err
   (
+ i->fld,
...)
Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/comedi_fops.c

@@ -2700,7 +2700,8 @@ struct comedi_device *comedi_alloc_board_minor(struct device *hardware_device)
 		mutex_unlock(&dev->mutex);
 		comedi_device_cleanup(dev);
 		comedi_dev_put(dev);
-		pr_err("ran out of minor numbers for board device files\n");
+		dev_err(hardware_device,
+			"ran out of minor numbers for board device files\n");
 		return ERR_PTR(-EBUSY);
 	}
 	dev->minor = i;
@@ -2753,7 +2754,8 @@ int comedi_alloc_subdevice_minor(struct comedi_subdevice *s)
 	}
 	mutex_unlock(&comedi_subdevice_minor_table_lock);
 	if (i == COMEDI_NUM_SUBDEVICE_MINORS) {
-		pr_err("ran out of minor numbers for subdevice files\n");
+		dev_err(dev->class_dev,
+			"ran out of minor numbers for subdevice files\n");
 		return -EBUSY;
 	}
 	i += COMEDI_NUM_BOARD_MINORS;