dm: adc: add iMX93 ADC support

This commit adds driver for iMX93 ADC.

The driver is implemented using driver model and provides
ADC uclass's methods for ADC single channel operations:
    - adc_start_channel()
    - adc_channel_data()
    - adc_stop()

ADC features:
    - channels: 4
    - resolution: 12-bit

Signed-off-by: Luca Ellero <l.ellero@asem.it>
Reviewed-by: Haibo Chen <haibo.chen@nxp.com>
diff --git a/drivers/adc/Makefile b/drivers/adc/Makefile
index c1387f3..5336c82 100644
--- a/drivers/adc/Makefile
+++ b/drivers/adc/Makefile
@@ -10,3 +10,4 @@
 obj-$(CONFIG_SARADC_ROCKCHIP) += rockchip-saradc.o
 obj-$(CONFIG_SARADC_MESON) += meson-saradc.o
 obj-$(CONFIG_STM32_ADC) += stm32-adc.o stm32-adc-core.o
+obj-$(CONFIG_ADC_IMX93) += imx93-adc.o