ASoC: remove duplicate definition of dapm_widgets/num_dapm_widgets

snd_soc_component and snd_soc_component_driver both have
dapm_widgets/num_dapm_widgets, but these are duplicated.
Let's remove duplicated definition.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>