thermal: armada: Remove support for A375-Z1 SoC

The Armada 375 Z1 SoC revision is no longer supported. This commit
removes the quirk needed for the thermal sensor.

Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>