libcamera: device_enumerator: add DeviceMatch class

Provide a DeviceMatch class which represents all properties of a media
device a pipeline hander can specify when searching for a device to use
in its pipeline.

Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/libcamera/include/device_enumerator.h

@@ -39,6 +39,20 @@ private:
 	std::map<std::string, std::string> entities_;
 };
 
+class DeviceMatch
+{
+public:
+	DeviceMatch(const std::string &driver);
+
+	void add(const std::string &entity);
+
+	bool match(const DeviceInfo *info) const;
+
+private:
+	std::string driver_;
+	std::vector<std::string> entities_;
+};
+
 } /* namespace libcamera */
 
 #endif	/* __LIBCAMERA_DEVICE_ENUMERATOR_H__ */