libcamera: timer: Remove the interval() method

The libcamera timers are single-shot timers. They are started with a
duration, but fire once only, not based on an interval. Remove the
interval concept by removing the interval() method, and rename other
occurences of interval to duration.

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

include/libcamera/timer.h

@@ -24,11 +24,10 @@ public:
 	~Timer();
 
 	void start(unsigned int msec) { start(std::chrono::milliseconds(msec)); }
-	void start(std::chrono::milliseconds interval);
+	void start(std::chrono::milliseconds duration);
 	void stop();
 	bool isRunning() const;
 
-	std::chrono::milliseconds interval() const { return interval_; }
 	std::chrono::steady_clock::time_point deadline() const { return deadline_; }
 
 	Signal<Timer *> timeout;
@@ -40,7 +39,6 @@ private:
 	void registerTimer();
 	void unregisterTimer();
 
-	std::chrono::milliseconds interval_;
 	std::chrono::steady_clock::time_point deadline_;
 };