Libport.Asio: more locks
Libport.Asio: more locks

	* lib/libport/asio-impl.hxx (continueWrite): Use a block lock on
	callbackLock.
	Make it more allike onReadDemux.

aldebaran/libport,aldebaran/libport,aldebaran/libport,aldebaran/libport,aldebaran/libport