thermal: Rename generate_netlink_event

It doesn't seem right for the thermal subsystem to export a symbol
named generate_netlink_event. This function is thermal-specific and
its name should reflect that fact. Rename it to
thermal_generate_netlink_event.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: R.Durgadoss <durgadoss.r@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>