libcamera: media_device: Make getEntityByName() const

The function does not modify the instance state. Mark it as const.

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

src/libcamera/include/media_device.h

@@ -38,7 +38,7 @@ public:
 	const std::string devnode() const { return devnode_; }
 
 	const std::vector<MediaEntity *> &entities() const { return entities_; }
-	MediaEntity *getEntityByName(const std::string &name);
+	MediaEntity *getEntityByName(const std::string &name) const;
 
 private:
 	std::string driver_;