libcamera: pipeline: ipu3: Fix argument name mismatch

Fix an argument name mismatch between method declaration and
definition.

Reported-by: Paul Elder <paul.elder@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>

src/libcamera/pipeline/ipu3/ipu3.cpp

@@ -122,7 +122,7 @@ public:
 	BufferPool *exportBuffers();
 	void freeBuffers();
 
-	int start(std::vector<std::unique_ptr<Buffer>> *buffer);
+	int start(std::vector<std::unique_ptr<Buffer>> *buffers);
 	int stop();
 
 	static int mediaBusToFormat(unsigned int code);