audio: set downmix default type to LO/RO. [1/1]

PD#SWPL-195747

Problem:
when dap enable, speaker output downmix type is forced to
LO/RO, but headphone default downmix type is LT/RT.

Solution:
set downmix default type to LO/RO.

Verify:
t6d

Change-Id: I885f363aed03f054a240fc865c79895cd5a2c491
Signed-off-by: wei.du <wei.du@amlogic.com>
2 files changed