ARM: dts: msm: Add energy costs for SDM660

Add cpu and cluster energy costs with available frequencies for SDM660
these are used by energy aware scheduler in task placement decisions.

Change-Id: I5756e80656be525937f9d0ec05649acdef42c2bf
Signed-off-by: Asha Magadi Venkateshamurthy <amagad@codeaurora.org>