hw/sensor/tmp105: Lower 4 bit of limit registers are always 0

hw/sensor/tmp105: Lower 4 bit of limit registers are always 0

Per datasheet, "HIGH AND LOW LIMIT REGISTERS", the lower 4 bit
of the limit registers are unused and always report 0.
The lower 4 bit should not be used for temperature comparisons,
so mask the unused bits before storing the limits.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20240906154911.86803-6-philmd@linaro.org>
[PMD: Update tests/qtest/ files]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>