thunderbolt: Check return value of kmemdup() in icm_handle_event()

kmemdup() may return NULL if there is not enough memory available. Check
this and bail out early in this case. While there move INIT_WORK() to
happen after we have allocated all the memory needed for the event
handling to avoid doing unnecessary work.

Signed-off-by: Xiaoke Wang <[e-mail]>
Signed-off-by: Mika Westerberg <[e-mail]>

drivers/thunderbolt/icm.c

···
 	if (!n)
 		return;
 
-	INIT_WORK(&n->work, icm_handle_notification);
 	n->pkg = kmemdup(buf, size, GFP_KERNEL);
+	if (!n->pkg) {
+		kfree(n);
+		return;
+	}
+
+	INIT_WORK(&n->work, icm_handle_notification);
 	n->tb = tb;
 
 	queue_work(tb->wq, &n->work);