v1.6

Changes since rc3
o Various fixes for SDW and DSM.

Features
Initial list of high level features that needs expanded with more details for v1.6 final.
o Intel Tigerlake CPUs
o Maxim Smart Amplifiers
o Beamformer microphone support.
o DC blocker audio processing component.
o Support for Zephyr RTOS.
o Major feature and performance improvements for ASRC, KWD and FIR/IIR components..
o Numerous bug fixes and performance improvements for Intel and NXP platforms.

Binaries
Signed binaries to follow shortly. Will be announced on ALSA list too and uploaded to sof-bin repo.