ARM: dts: msm: disable SPMI debug bus for sdm845v1

Disable the SPMI PMIC arbiter debug bus on SDM845v1 boards as it
has been repurposed for a workaround.

Change-Id: Iffacdf80f103b2af095718631f7db6eecdbaaef0
Signed-off-by: David Collins <collinsd@codeaurora.org>