USB: serial: clean up attribute permissions

Clean up the DEVICE_ATTR usage in the USB serial drivers, making them
more obvious as to the permissions that the sysfs files should be.

Note: ftdi_sio.c still has a DEVICE_ATTR() used, that will have to wait
until after 3.12-rc1 comes out when DEVICE_ATTR_WO() shows up in Linus's
tree.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/serial/iuu_phoenix.c b/drivers/usb/serial/iuu_phoenix.c
index 790673e..57c439a 100644
--- a/drivers/usb/serial/iuu_phoenix.c
+++ b/drivers/usb/serial/iuu_phoenix.c
@@ -1130,7 +1130,7 @@
  * Sysfs Attributes
  */
 
-static ssize_t show_vcc_mode(struct device *dev,
+static ssize_t vcc_mode_show(struct device *dev,
 	struct device_attribute *attr, char *buf)
 {
 	struct usb_serial_port *port = to_usb_serial_port(dev);
@@ -1139,7 +1139,7 @@
 	return sprintf(buf, "%d\n", priv->vcc);
 }
 
-static ssize_t store_vcc_mode(struct device *dev,
+static ssize_t vcc_mode_store(struct device *dev,
 	struct device_attribute *attr, const char *buf, size_t count)
 {
 	struct usb_serial_port *port = to_usb_serial_port(dev);
@@ -1163,9 +1163,7 @@
 fail_store_vcc_mode:
 	return count;
 }
-
-static DEVICE_ATTR(vcc_mode, S_IRUSR | S_IWUSR, show_vcc_mode,
-	store_vcc_mode);
+static DEVICE_ATTR_RW(vcc_mode);
 
 static int iuu_create_sysfs_attrs(struct usb_serial_port *port)
 {