ASoC: rt715: remove kcontrols which no longer be used

Using new kcontrols "Capture Switch" and "Capture Volume" instead,
remove kcontrols which no longer be used.

Signed-off-by: Jack Yu <jack.yu@realtek.com>
Link: https://lore.kernel.org/r/5c314f5512654aca9fff0195f77264de@realtek.com
Signed-off-by: Mark Brown <broonie@kernel.org>