msm: thermal: Add MSM thermal sensing and limiting

Add a thermal driver to poll and detect any thermal condition at boot
and limit max cpu frequency on a thermal condition. This driver is
intended to limit cpu thermal output until the userspace thermald
kicks in. The thermald will disable this driver and take over the
cpu thermal sensing and mitigation.

Change-Id: I2710bfdeb5bf01c864437e13da835621d1b9202c
Signed-off-by: Praveen Chidambaram <pchidamb@codeaurora.org>
Signed-off-by: David Brown <davidb@codeaurora.org>