ASoC: rt5645: fix IRQ error in jack detection

IRQ of jack and button detection is abnormal if "LDO2" and
"Mic Det Power" power disable in rt5645_jack_detect.
This patch make these two power keep enabled until jack out.

Signed-off-by: John Lin <john.lin@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>