ARM: dts: msm: Add a slimbus instance for SDM845

Add the SLIMbus instance that is used to enable BT/FM
functionality.

CRs-Fixed: 2002163
Change-Id: I4044ea8e76fd2552c6918dcabf95fdc70aa660b8
Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org>