libcamera: buffer: Remove copyFrom()

There are no user left of the copyFrom() operation, remove it.

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

include/libcamera/buffer.h

@@ -57,8 +57,6 @@ public:
 
 	unsigned int cookie() const { return cookie_; }
 	void setCookie(unsigned int cookie) { cookie_ = cookie; }
-
-	int copyFrom(const FrameBuffer *src);
 private:
 	friend class Request; /* Needed to update request_. */
 	friend class V4L2VideoDevice; /* Needed to update metadata_. */