ASoC: msm: qdsp6v2: support ULLPP stream type

Audio Stream Manager now supports ultra low latency
stream with post processing capability. Update
device tree definition of PCM platform driver to allow
ullpp stream type

Change-Id: I36f2f9ca5780a21a07bbdc19c6f8b743d48b7859
Signed-off-by: Patrick Lai <plai@codeaurora.org>
Signed-off-by: Banajit Goswami <bgoswami@codeaurora.org>