usb: misc: adutux: remove redundant error check on copy_to_user return code

The 2nd check for a non-zero return from copy_to_user is redundant as
it is has already been made a few lines earlier.  This check was made
redundant because of previous fix to the copy_to_user error return
check.

Detected by CoverityScan, CID#114347 ("Logically Dead Code")

Fixes: 1865a9c3 ("USB: adutux: fix misuse of return value of copy_to_user()")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/misc/adutux.c

@@ -389,10 +389,6 @@ static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
 			dev->secondary_head += (amount - i);
 			bytes_read += (amount - i);
 			bytes_to_read -= (amount - i);
-			if (i) {
-				retval = bytes_read ? bytes_read : -EFAULT;
-				goto exit;
-			}
 		} else {
 			/* we check the primary buffer */
 			spin_lock_irqsave (&dev->buflock, flags);