thermal: int340x: New Interface to read trip and notify

Separated the code for reading trip points from int340x_thermal_zone_add to
a standalone function int340x_thermal_read_trips. This standlone
interface to read is exported so that int340x drivers can re-read trips
on ACPI notification for trip point change.
Also the appropriate notification events are sent by int340x driver based
on the acpi event using int340x_thermal_zone_device_update().

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>