libcamera: request: Add hasPendingBuffers() method

Add method to verify if a request has pending buffers yet to be
completed.

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

include/libcamera/request.h

@@ -37,6 +37,8 @@ public:
 
 	Status status() const { return status_; }
 
+	bool hasPendingBuffers() const { return !pending_.empty(); }
+
 private:
 	friend class Camera;
 	friend class PipelineHandler;