Fix vol/mic toggle buttons

They were suffering from double-connection syndrom, and the way muting worked was now conflicting with how the output sound level setting works

Fixes #1442

src/core/coreav.cpp

@@ -244,7 +244,7 @@ void Core::playCallAudio(void* toxav, int32_t callId, const int16_t *data, uint1
 {
     Q_UNUSED(user_data);
 
-    if (!calls[callId].active)
+    if (!calls[callId].active || calls[callId].muteVol)
         return;
 
     if (!calls[callId].alSource)
@@ -356,10 +356,7 @@ void Core::micMuteToggle(int32_t callId)
 void Core::volMuteToggle(int32_t callId)
 {
     if (calls[callId].active)
-    {
         calls[callId].muteVol = !calls[callId].muteVol;
-        alSourcef(calls[callId].alSource, AL_GAIN, calls[callId].muteVol ? 0.f : 1.f);
-    }
 }
 
 void Core::onAvCancel(void* _toxav, int32_t callId, void* core)

src/widget/form/chatform.cpp

@@ -91,8 +91,6 @@ ChatForm::ChatForm(Friend* chatFriend)
     connect(videoButton, &QPushButton::clicked, this, &ChatForm::onVideoCallTriggered);
     connect(msgEdit, &ChatTextEdit::enterPressed, this, &ChatForm::onSendTriggered);
     connect(msgEdit, &ChatTextEdit::textChanged, this, &ChatForm::onTextEditChanged);
-    connect(micButton, SIGNAL(clicked()), this, SLOT(onMicMuteToggle()));
-    connect(volButton, SIGNAL(clicked()), this, SLOT(onVolMuteToggle()));
     connect(Core::getInstance(), &Core::fileSendFailed, this, &ChatForm::onFileSendFailed);
     connect(this, SIGNAL(chatAreaCleared()), getOfflineMsgEngine(), SLOT(removeAllReciepts()));
     connect(&typingTimer, &QTimer::timeout, this, [=]{