Move test applications to src/apps/

The cam and qcam test application share code, currently through a crude
hack that references the cam source files directly from the qcam
meson.build file. To prepare for the introduction of hosting that code
in a static library, move all applications to src/apps/.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/apps/qcam/message_handler.h

@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2020, Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *
+ * message_handler.cpp - qcam - Log message handling
+ */
+
+#pragma once
+
+#include <QtGlobal>
+
+class MessageHandler
+{
+public:
+	MessageHandler(bool verbose);
+
+private:
+	static void handleMessage(QtMsgType type,
+				  const QMessageLogContext &context,
+				  const QString &msg);
+
+	static QtMessageHandler handler_;
+	static bool verbose_;
+};