libcamera: pipeline: Drop forward declaration of BufferPool

There is no need to forward declare BufferPool, drop it.

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

src/libcamera/include/pipeline_handler.h

@@ -21,7 +21,6 @@
 namespace libcamera {
 
 class Buffer;
-class BufferPool;
 class Camera;
 class CameraConfiguration;
 class CameraManager;