libcamera: ipu3: Remove streams from IPU3CameraConfiguration

The IPU3CameraConfiguration::streams_ field was used to keep an
association between the StreamConfiguration and the assigned streams
before CameraConfiguration::setStream() was called at configure() time.

The stream assignment was based on the order in which elements were
inserted in the vector, implementing a fragile association between
streams and their intended configurations.

As it is now possible to assign streams at validation time, there is no
need to keep that association in place, and the streams_ vector is now
unused.

Remove it and the associated accessor method from the
IPU3CameraConfiguration class.

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

src/libcamera/pipeline/ipu3/ipu3.cpp

@@ -67,7 +67,6 @@ public:
 	Status validate() override;
 
 	const StreamConfiguration &cio2Format() const { return cio2Configuration_; };
-	const std::vector<const Stream *> &streams() { return streams_; }
 
 private:
 	/*
@@ -79,7 +78,6 @@ private:
 	const IPU3CameraData *data_;
 
 	StreamConfiguration cio2Configuration_;
-	std::vector<const Stream *> streams_;
 };
 
 class PipelineHandlerIPU3 : public PipelineHandler