thermal/drivers/hisi: Use platform_get_irq_byname

As we have the interrupt names defines, replace platform_get_irq() by
platform_get_irq_byname(), so no confusion can be made when getting
the interrupt with the sensor id.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>