xen/evtchn: Fix name of Xen event-channel device

The Xen event-channel device is named evtchn in the kernel but always
used as /dev/xen/evtchn in userspace. This patch fixes the name.
Signed-off-by: NBastian Blank <waldi@debian.org>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

drivers/xen/evtchn.c

@@ -517,7 +517,7 @@ static const struct file_operations evtchn_fops = {
 
 static struct miscdevice evtchn_miscdev = {
 	.minor        = MISC_DYNAMIC_MINOR,
-	.name         = "evtchn",
+	.name         = "xen/evtchn",
 	.fops         = &evtchn_fops,
 };
 static int __init evtchn_init(void)