staging: frontier: alphatrack.c: remove err() usage

err() was a very old USB-specific macro that I thought had
gone away.  This patch removes it from being used in the
driver and uses dev_err() instead.

CC: "David Täht" <d@teklibre.com>
CC: Hitoshi Nakamori <hitoshi.nakamori@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/frontier/alphatrack.c

@@ -333,8 +333,8 @@ static int usb_alphatrack_open(struct inode *inode, struct file *file)
 	interface = usb_find_interface(&usb_alphatrack_driver, subminor);
 
 	if (!interface) {
-		err("%s - error, can't find device for minor %d\n",
-		    __func__, subminor);
+		printk(KERN_ERR "%s - error, can't find device for minor %d\n",
+		       __func__, subminor);
 		retval = -ENODEV;
 		goto unlock_disconnect_exit;
 	}
@@ -494,7 +494,8 @@ static ssize_t usb_alphatrack_read(struct file *file, char __user *buffer,
 	/* verify that the device wasn't unplugged */
 	if (dev->intf == NULL) {
 		retval = -ENODEV;
-		err("No device or device unplugged %d\n", retval);
+		printk(KERN_ERR "%s: No device or device unplugged %d\n",
+		       __func__, retval);
 		goto unlock_exit;
 	}
 
@@ -564,7 +565,8 @@ static ssize_t usb_alphatrack_write(struct file *file,
 	/* verify that the device wasn't unplugged */
 	if (dev->intf == NULL) {
 		retval = -ENODEV;
-		err("No device or device unplugged %d\n", retval);
+		printk(KERN_ERR "%s: No device or device unplugged %d\n",
+		       __func__, retval);
 		goto unlock_exit;
 	}
 
@@ -599,7 +601,7 @@ static ssize_t usb_alphatrack_write(struct file *file,
 	}
 
 	if (dev->interrupt_out_endpoint == NULL) {
-		err("Endpoint should not be be null!\n");
+		dev_err(&dev->intf->dev, "Endpoint should not be be null!\n");
 		goto unlock_exit;
 	}
 
@@ -619,7 +621,8 @@ static ssize_t usb_alphatrack_write(struct file *file,
 	retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
 	if (retval) {
 		dev->interrupt_out_busy = 0;
-		err("Couldn't submit interrupt_out_urb %d\n", retval);
+		dev_err(&dev->intf->dev,
+			"Couldn't submit interrupt_out_urb %d\n", retval);
 		atomic_dec(&dev->writes_pending);
 		goto unlock_exit;
 	}