ARM: dts: msm: Update the cpu node names for SDM845

Match the node names to mpir values, kernel debug messages use the node
name and the mismatch with mpidr creates confusion while analyzing the
logs.

Change-Id: Id8ac33dc3ea560b5d775528072bc958ae8793e5a
Signed-off-by: Channagoud Kadabi <ckadabi@codeaurora.org>