Delete obsolete class methods and update related code

Delete obsolete methods from QAudioFormat and QAudioDeviceInfo
and update code that relied on the obsolete methods.

Change-Id: I007e36375a45399b1d5a289341bc5d5a05dc68cc
Reviewed-by: Michael Goddard <michael.goddard@nokia.com>

src/imports/audioengine/qaudioengine_openal_p.cpp

@@ -171,7 +171,7 @@ public Q_SLOTS:
             return;
         }
         alBufferData(m_alBuffer, alFormat, m_sample->data().data(),
-                     m_sample->data().size(), m_sample->format().frequency());
+                     m_sample->data().size(), m_sample->format().sampleRate());
 
         if (!QAudioEnginePrivate::checkNoError("fill buffer")) {
             return;