libcamera: framebuffer: Make FrameBuffer::cancel() private

FrameBuffer::cancel() is not meant to be used by applications. Move it
to the FrameBuffer::Private class.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Dorota Czaplejewicz <dorota.czaplejewicz@puri.sm>
[Kieran: Handle rebase]
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/libcamera/framebuffer.cpp

@@ -186,6 +186,14 @@ FrameBuffer::Private::~Private()
  * fence and handle it opportunely before using the buffer again.
  */
 
+/**
+ * \fn FrameBuffer::Private::cancel()
+ * \brief Marks the buffer as cancelled
+ *
+ * If a buffer is not used by a request, it shall be marked as cancelled to
+ * indicate that the metadata is invalid.
+ */
+
 /**
  * \class FrameBuffer
  * \brief Frame buffer data and its associated dynamic metadata
@@ -407,12 +415,4 @@ std::unique_ptr<Fence> FrameBuffer::releaseFence()
 	return std::move(_d()->fence_);
 }
 
-/**
- * \fn FrameBuffer::cancel()
- * \brief Marks the buffer as cancelled
- *
- * If a buffer is not used by a request, it shall be marked as cancelled to
- * indicate that the metadata is invalid.
- */
-
 } /* namespace libcamera */