ASoC: rt5670: Revert Keep sysclk on patch

The "Keep sysclk on if JD func is used" patch force enable/disable
pin in rt5670_set_dai_sysclk. But some machine driver call it in
dapm widget event. It will cause kernel crash.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>