drivers/iio/adc/ad9361: Use devm_gpiod and name the reset gpio

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
drivers/iio/adc/ad9361: Add RX2 Phase inversion option

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
drivers/iio/adc/ad9361: Add Multi Chip Sync (MCS) Support

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>