ipa: Switch to FrameBuffer interface

Switch the IPA interfaces and implementations to use the Framebuffer
interface.

- The IPA interface is switched to use the simpler FrameBuffer::Plane
  container when carrying dmabuf descriptions (fd and length) over the
  pipeline/IPA boundary.

- The RkISP1 IPA implementation takes advantage of the new simpler and
  safer (better control over file descriptors) FrameBuffer interface.

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

include/ipa/ipa_interface.h

@@ -105,7 +105,7 @@ struct IPAStream {
 
 struct IPABuffer {
 	unsigned int id;
-	BufferMemory memory;
+	std::vector<FrameBuffer::Plane> planes;
 };
 
 struct IPAOperationData {