ARM: dts: msm: Add the debug clock node for SM6150

Add debug clock controller node to use the debug
clock controller driver for measuring the clocks.
Also add the parent supply for CX GDSC to enable
the parent supply before turning on CX GDSC.

Change-Id: Icd5bdabedac06ee2414369f492cf738a2dfa62eb
Signed-off-by: Odelu Kukatla <okukatla@codeaurora.org>