uapi: sound: move necessary sound headers under uapi

Now all uapi header are exported as per
("uapi: export all headers under uapi directories")
but some header files are under "include/sound" and
its not exported so userspace build is failing.
move necessary sound headers under uapi to avoid build
failure and make it align with base.

Change-Id: I08a465a6a3837c4bcf32c5d9983ba4837d603df2
Signed-off-by: Swetha Chikkaboraiah <schikk@codeaurora.org>