msm: pil: Move sending NMI to QDSP from the pil-q6v5-lpass driver

The SCM call to send NMI to QDSP is made from the audio
driver instead of from the pil-q6v5-lpass driver.

The audio driver uses the panic notifier and the
'before_shutdown' subsystem notification to make the call.
This is crucial in moving the pil-q6v5-lpass driver to use
the generic PIL driver functionality.

CRs-Fixed: 625452

Change-Id: I468e0364a77f06175b5bd646215b369ba8007393
Signed-off-by: Deepak Katragadda <dkatraga@codeaurora.org>