Set the "realtek,in1-differential" or "realtek,in3-differential"
device-property when the BYT_RT5640_DIFF_MIC quirk is set instead of
directly poking the codec registers.

This also fixes the BYT_RT5640_DIFF_MIC quirk not working when
combined with BYT_RT5640_IN3_MAP.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NMark Brown <broonie@kernel.org>