[chat2] Fix resource unlock condition

If the resource of the updated presence is equal to the currently
locked resource, then no further action is required.

Thanks to Pedro Oliveira for reporting this.

Reported-by: Pedro Oliveira <kanytu@gmail.com>

smack-extensions/src/main/java/org/jivesoftware/smack/chat2/ChatManager.java

@@ -161,7 +161,7 @@ public final class ChatManager extends Manager {
                 }
 
                 final EntityFullJid fullFrom = from.asEntityFullJidIfPossible();
-                if (!chat.lockedResource.equals(fullFrom)) {
+                if (chat.lockedResource.equals(fullFrom)) {
                     return;
                 }