drivers: uio: remove redundant assignment to variable retval

The variable retval is being initialized with a value that is
never read and it is being updated later with a new value. The
initialization is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200425124448.139532-1-colin.king@canonical.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/uio/uio.c

@@ -398,7 +398,7 @@ static void uio_dev_del_attributes(struct uio_device *idev)
 
 static int uio_get_minor(struct uio_device *idev)
 {
-	int retval = -ENOMEM;
+	int retval;
 
 	mutex_lock(&minor_lock);
 	retval = idr_alloc(&uio_idr, idev, 0, UIO_MAX_DEVICES, GFP_KERNEL);