Thermal: Add a thermal notifier for user space

This patch registers a governor which will let the
user land manage the platform thermals. Whenever a
trip happens, this governor just notifies the user
space using kobj_uevent().

Signed-off-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>