ARM: multi_v7_defconfig: enable the Amlogic Meson ADC and eFuse drivers

With the SAR ADC driver ADC measurements can be taken though the IIO
framework. Additionally the SAR ADC has a channel which is connected to
an internal temperature sensor. The calibration data for this internal
temperature sensor is stored in the eFuse.

Enable the SAR ADC driver and the eFuse driver for the 32-bit Amlogic
Meson SoCs so we can expose the chip temperature to userspace through
the IIO hwmon driver (whose config option is already enabled:
CONFIG_SENSORS_IIO_HWMON=y).

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>