libcamera: controls: Avoid double lookups

Now that the ControlList::get() function returns an instance of
std::optional<>, we can replace the ControlList::contains() calls with a
nullopt check on the return value of get(). This avoids double lookups
of controls through the code base.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>

src/cam/main.cpp

@@ -300,8 +300,9 @@ std::string CamApp::cameraName(const Camera *camera)
 	 * Construct the name from the camera location, model and ID. The model
 	 * is only used if the location isn't present or is set to External.
 	 */
-	if (props.contains(properties::Location)) {
-		switch (*props.get(properties::Location)) {
+	const auto &location = props.get(properties::Location);
+	if (location) {
+		switch (*location) {
 		case properties::CameraLocationFront:
 			addModel = false;
 			name = "Internal front camera ";
@@ -316,12 +317,14 @@ std::string CamApp::cameraName(const Camera *camera)
 		}
 	}
 
-	if (addModel && props.contains(properties::Model)) {
+	if (addModel) {
 		/*
 		 * If the camera location is not availble use the camera model
 		 * to build the camera name.
 		 */
-		name = "'" + *props.get(properties::Model) + "' ";
+		const auto &model = props.get(properties::Model);
+		if (model)
+			name = "'" + *model + "' ";
 	}
 
 	name += "(" + camera->id() + ")";