libcamera: Declare empty virtual destructors as defaulted

The base class of polymorphic classes is required to declare a
destructor. Several of these are empty, and can thus be declared as
defaulted.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Umang Jain <email@uajain.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/libcamera/pipeline/rkisp1/timeline.h

@@ -22,7 +22,7 @@ public:
 	FrameAction(unsigned int frame, unsigned int type)
 		: frame_(frame), type_(type) {}
 
-	virtual ~FrameAction() {}
+	virtual ~FrameAction() = default;
 
 	unsigned int frame() const { return frame_; }
 	unsigned int type() const { return type_; }
@@ -38,7 +38,7 @@ class Timeline
 {
 public:
 	Timeline();
-	virtual ~Timeline() {}
+	virtual ~Timeline() = default;
 
 	virtual void reset();
 	virtual void scheduleAction(std::unique_ptr<FrameAction> action);