topology: docs: add func doxygen defs
topology: docs: add func doxygen defs

Signed-off-by: Liam Girdwood <1c687ae09fa7f11acd34075a0ae6b39df2be9341@linux.intel.com>

lgirdwood/alsa-lib,mengdonglin/alsa-lib,lgirdwood/alsa-lib,lgirdwood/alsa-lib,mengdonglin/alsa-lib,lgirdwood/alsa-lib,lgirdwood/alsa-lib,mengdonglin/alsa-lib,mengdonglin/alsa-lib,mengdonglin/alsa-lib