ARM: dts: msm: Add support for AANC for msm8226 QRD

Add routing for AMIC3 and AMIC4. Set micbias3 to
external. This will enable the paths for error and noise
mics which are needed for AANC algorithm.

Change-Id: Id5479b7a30767d9e73d3242aa05129da72589948
Signed-off-by: Damir Didjusto <damird@codeaurora.org>