ARM: dts: msm: add DT node for flash/torch LED for PMI Thorium

Add device tree node to enable flash and torch LED on PMI Thorium.
Flash LED supports flash light and torch light for camera and
other userspace apps.

Change-Id: I7d9f7e8d1985a86e0ad3b0a535c484d2c5ae29fc
Signed-off-by: Himanshu Aggarwal <haggarwa@codeaurora.org>