ARM: dts: msm: Add support for clock debug for MSMfalcon/MSMtriton

Clock debug mux node is required for global clock controller, CPU, graphics
clock controller and multimedia clock controller. Add syscon device nodes
for the required nodes.

Change-Id: Ie6571c7b780f184e6af78c3c339e51820a09dfa8
Signed-off-by: Taniya Das <tdas@codeaurora.org>