ARM: dts: msm: Fallback to 3 cluster approach for Katmai

There was issue reported that cpu7 is not scaling up
even when some load is given to it. This issue is fixed
falling back to 3 cluster approach making the cpu7
frequency scaling based on the load.

Change-Id: Ib9d681f7a356b957fdb8450003a0c71029ef1a6a