Fixed SPI config for ADC input. Also Fixed iio Dev number.

SPI comes up in an odd configuration and needs to be set into a valid config before you can read from the ADC, which is on the SPI bus. So set Pins 10-13 to input. These can be overridden later by the python code, but we need at least a good initial config. 

Also changed the iio device number from 0 to 1, as on the Arduino board it's now 1 fro the ADC iii driver. 

Signed-off-by: David Hunt <dave@davidhunt.ie>