Collect the related dbuf information into a struct.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210416171011.19012-2-ville.syrjala@linux.intel.comReviewed-by: NJani Nikula <jani.nikula@intel.com>