powerpc/pseries/vio: Don't return ENODEV if node or compatible missing

We noticed the following nuisance messages during boot process:

  vio vio: uevent: failed to send synthetic uevent
  vio 4000: uevent: failed to send synthetic uevent
  vio 4001: uevent: failed to send synthetic uevent
  vio 4002: uevent: failedto send synthetic uevent
  vio 4004: uevent: failed to send synthetic uevent

It's caused by either vio_register_device_node() failing to set
dev->of_node or the node is missing a "compatible" property. To match
the definition of modalias in modalias_show(), remove the return of
ENODEV in such cases. The failure messages is also suppressed with this
change.

Signed-off-by: Lidong Zhong <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

Author: ldzhong

arch/powerpc/platforms/pseries/vio.c

@@ -1592,13 +1592,9 @@ static int vio_hotplug(const struct device *dev, struct kobj_uevent_env *env)
 	const char *cp;
 
 	dn = dev->of_node;
-	if (!dn)
-		return -ENODEV;
-	cp = of_get_property(dn, "compatible", NULL);
-	if (!cp)
-		return -ENODEV;
+	if (dn && (cp = of_get_property(dn, "compatible", NULL)))
+		add_uevent_var(env, "MODALIAS=vio:T%sS%s", vio_dev->type, cp);
 
-	add_uevent_var(env, "MODALIAS=vio:T%sS%s", vio_dev->type, cp);
 	return 0;
 }