thermal: core: remove unnecessary device_remove() calls

Given that cdevs sysfs properties are already registered using
the dev.groups, there is no need to explicitly call device_remove()
for each property.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>