ARM: dts: msm: Add coresight devices for MSMSKUNK

Add device tree for coresight devices. Coresight
device path from STM source to ETR sink is added to the device
tree. The path is needed to configure and enable STM logging.

Change-Id: I318d0ea9756d9c05705941c5e81da140fa926458
Signed-off-by: Satyajit Desai <sadesai@codeaurora.org>