libcamera: pipeline: ipu3: Initialise pixel format to NV12 in new config

To avoid printing debugging messages related to stream configuration
adjustement when generating a new configuration, set the pixel format
explicitly instead of relying on the internal validate() call to do so.

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

src/libcamera/pipeline/ipu3/ipu3.cpp

@@ -402,6 +402,8 @@ CameraConfiguration *PipelineHandlerIPU3::generateConfiguration(Camera *camera,
 		StreamConfiguration cfg = {};
 		IPU3Stream *stream = nullptr;
 
+		cfg.pixelFormat = V4L2_PIX_FMT_NV12;
+
 		switch (role) {
 		case StreamRole::StillCapture:
 			/*