iio: adc: add IMX7D ADC driver support

Freescale i.MX7D soc contains a new ADC IP. This patch add this ADC
driver support, and the driver only support ADC software trigger.

Signed-off-by: Haibo Chen <haibo.chen@freescale.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
3 files changed