Revert adding dispatchLocker to QDBusConnection::connect

This reverts 268cc1dc99

On further examination it has shown that even if it fixes one deadlock
it is either creating some others or making existing ones happen more often

Change-Id: I70068cf0b0435a5dc06d4ac77ea50d3ba2361d01
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/dbus/qdbusconnection.cpp

@@ -700,7 +700,6 @@ bool QDBusConnection::connect(const QString &service, const QString &path, const
         return false;
     }
 
-    QDBusDispatchLocker dispatchLocker(ConnectAction, d);
     QDBusWriteLocker locker(ConnectAction, d);
     return d->connectSignal(service, path, interface, name, argumentMatch, signature, receiver, slot);
 }