call: close audio at the end of a call

hangupCall() remove the calls in a dht pool. This means that the
operation can take quite some time. So, checkAudio() should be
done once the call is removed. In the other case, the audio layer
will remains open forever

Change-Id: Ia28c99001989215045389e141f694e7732bfcd1d

src/call.cpp

@@ -152,6 +152,7 @@ Call::removeCall()
     setState(CallState::OVER);
     if (Recordable::isRecording())
         Recordable::stopRecording();
+    Manager::instance().checkAudio();
 }
 
 const std::string&

src/manager.cpp

@@ -1028,7 +1028,6 @@ Manager::hangupCall(const std::string& callId)
 
     try {
         call->hangup(0);
-        checkAudio();
     } catch (const VoipLinkException &e) {
         JAMI_ERR("%s", e.what());
         return false;
@@ -1190,8 +1189,6 @@ Manager::refuseCall(const std::string& id)
 
     call->refuse();
 
-    checkAudio();
-
     pimpl_->removeWaitingCall(id);
 
     // Disconnect streams