ARM: dts: msm: Add KTM cluster related information for MSM8939

Add synchronous cluster information and property to enable
onlining hotplugged cores feature in KTM for MSM8939.

Change-Id: I8d26f9c9b2e3cefc3432226d98c4bd0d3885092c
Signed-off-by: Manaf Meethalavalappu Pallikunhi <manafm@codeaurora.org>