xen/xenbus: make DEVICE_ATTR()s static

They don't need to be global, and may cause linker clashes.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>

drivers/xen/xenbus/xenbus_probe.c

@@ -454,21 +454,21 @@ static ssize_t xendev_show_nodename(struct device *dev,
 {
 	return sprintf(buf, "%s\n", to_xenbus_device(dev)->nodename);
 }
-DEVICE_ATTR(nodename, S_IRUSR | S_IRGRP | S_IROTH, xendev_show_nodename, NULL);
+static DEVICE_ATTR(nodename, S_IRUSR | S_IRGRP | S_IROTH, xendev_show_nodename, NULL);
 
 static ssize_t xendev_show_devtype(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
 	return sprintf(buf, "%s\n", to_xenbus_device(dev)->devicetype);
 }
-DEVICE_ATTR(devtype, S_IRUSR | S_IRGRP | S_IROTH, xendev_show_devtype, NULL);
+static DEVICE_ATTR(devtype, S_IRUSR | S_IRGRP | S_IROTH, xendev_show_devtype, NULL);
 
 static ssize_t xendev_show_modalias(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
 	return sprintf(buf, "xen:%s\n", to_xenbus_device(dev)->devicetype);
 }
-DEVICE_ATTR(modalias, S_IRUSR | S_IRGRP | S_IROTH, xendev_show_modalias, NULL);
+static DEVICE_ATTR(modalias, S_IRUSR | S_IRGRP | S_IROTH, xendev_show_modalias, NULL);
 
 int xenbus_probe_node(struct xen_bus_type *bus,
 		      const char *type,