Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h
index 936c0b3..05847eb 100644
--- a/drivers/net/xen-netback/common.h
+++ b/drivers/net/xen-netback/common.h
@@ -248,6 +248,22 @@
 	struct xenvif_hash_cache cache;
 };
 
+struct backend_info {
+	struct xenbus_device *dev;
+	struct xenvif *vif;
+
+	/* This is the state that will be reflected in xenstore when any
+	 * active hotplug script completes.
+	 */
+	enum xenbus_state state;
+
+	enum xenbus_state frontend_state;
+	struct xenbus_watch hotplug_status_watch;
+	u8 have_hotplug_status_watch:1;
+
+	const char *hotplug_script;
+};
+
 struct xenvif {
 	/* Unique identifier for this interface. */
 	domid_t          domid;
@@ -283,6 +299,8 @@
 	struct xenbus_watch credit_watch;
 	struct xenbus_watch mcast_ctrl_watch;
 
+	struct backend_info *be;
+
 	spinlock_t lock;
 
 #ifdef CONFIG_DEBUG_FS