drivers: sensors: nxp: kinetis: temp: select CONFIG_ADC

The NXP Kinetis temperature sensor depends on CONFIG_ADC. Make the driver
Kconfig select CONFIG_ADC to get better CI coverage (enabling the driver
when CONFIG_SENSOR is enabled without depending on CONFIG_ADC=y).

Signed-off-by: Henrik Brix Andersen <hebad@vestas.com>