thermal/drivers/acerhdf: Remove pointless governor test

The thermal zone parameter specifies the bang-bang governor.

The Kconfig selects the bang-bang governor. So it is pointless to test
if the governor was set for the thermal zone assuming it may not have
been compiled-in.

Remove the test and prevent another access into the thermal internals.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Peter Kaestle <peter@piie.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>