ASoC: msm: Add hwdep node for NOIRQ FE

ALSA lacks support to accept shared memory supplied
from userspace. But some usecases need to get a shareable
file descriptor for the dma buffer. As an alternate
to adding custom ioctls to the ALSA framework, use
a hwdep node to get a file descriptor to the underlying dma buffer.
Maintain compat mode as well.

CRs-Fixed: 2041151
Change-Id: Id783bb84e8ef59b28e42d982903971625577b9a3
Signed-off-by: Haynes Mathew George <hgeorge@codeaurora.org>