ARM: dts: msm: Update cpu idle costs in energy costs for sdm670

SDM670 supports maximum of 4 low power modes for cpus, but energy-costs
data has only 4 idle states instead of 5 (1 (nr_run=0) + 4 lpm).

Update energy-costs to include all low power modes in its idle-costs.

Change-Id: I1c65215bcb2b89611b1f4dce6798ff5c3037915a
Signed-off-by: Lingutla Chandrasekhar <clingutla@codeaurora.org>