libcamera: pipeline: simple: Use MediaLink string helper

Replace the open-coded implementation of a link representation
with the operator<< overload string representation to simplify
the code and unify appearance of reporting MediaLinks.

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

src/libcamera/pipeline/simple/simple.cpp

@@ -773,11 +773,8 @@ int SimpleCameraData::setupFormats(V4L2SubdeviceFormat *format,
 		}
 
 		LOG(SimplePipeline, Debug)
-			<< "Link '" << source->entity()->name()
-			<< "':" << source->index()
-			<< " -> '" << sink->entity()->name()
-			<< "':" << sink->index()
-			<< " configured with format " << *format;
+			<< "Link " << *link << ": configured with format "
+			<< *format;
 	}
 
 	return 0;