arm/dt: msm8610: Add kernel thermal mitigation device

Add kernel thermal mitigation device. Kernel thermal mitigation provides
basic thermal protection during boot until the full fledged userspace
thermal mitigation takes over.

Change-Id: I89d394ae8504df234528204c9e78bef457ce5b1e
Signed-off-by: Jennifer Liu <chihning@codeaurora.org>