ARM: dts: msm: Update PCM device node to ULLPP mode for MSM8996

Update PCM device node with ID 1 from low latency mode to
ultra low latency with post-processing support as ULLPP mode
incurs less latency overhead while support tuning. Given this
PCM device node is targeted for key tone and general low latency
audio application, additional functionality offered by low latency
mode in audio stream manager in application DSP is not required.

Change-Id: I2e16186e963f7e980cb7affa20e83f886c1384a4
Signed-off-by: Patrick Lai <plai@codeaurora.org>