libcamera: media_device: Use Loggable interface

Extend MediaDevice to inherit from the Loggable interface to support a
logPrefix which presents the device node path, and the driver name.

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

src/libcamera/media_device.cpp

@@ -75,6 +75,11 @@ MediaDevice::~MediaDevice()
 	clear();
 }
 
+std::string MediaDevice::logPrefix() const
+{
+	return deviceNode() + "[" + driver() + "]";
+}
+
 /**
  * \brief Claim a device for exclusive use
  *