hikey960: Add hifi dsp audio example of increasing PCM Gain

In this example output stream buffer is send to DSP through
HIFI_MISC_IOCTL_PCM_GAIN Ioctl for increasing gain.

Bug: 64395692
Test: Manual

Change-Id: I1e931d985335d6d236c0edf84978170f651feffd
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
1 file changed