GstVaapiMiniObject and GstVaapiObject are deprecrated. This is the
first step to remove them, by porting GstVaapiImage as a
GstMiniObject.
Signed-off-by: Víctor Manuel Jáquez Leal <vjaquez@igalia.com>
Don't expose functions that reference a GstVaapiImageRaw, those are
meant to be internal only for implementing subpictures sync. Also add
a few private definitions to avoid functions calls for retrieving
image size and format information.
