applications: nrf_desktop: Align battery_def.h with nrfx 4.0

Change aligns battery_def.h configuration files used by nRF Desktop
devices with nrfx 4.0. `NRF_SAADC_` macros can no longer be used here.

Jira: NCSDK-36662

Signed-off-by: Marek Pieta <[email protected]>
Signed-off-by: Jakub Zymelka <[email protected]>
(cherry picked from commit 89bc0c0)

Author: MarekPieta

applications/nrf_desktop/configuration/nrf52840gmouse_nrf52840/battery_def.h

@@ -8,12 +8,15 @@
  * and holds information about battery characteristic.
  */
 
+#include <helpers/nrfx_analog_common.h>
+#include <zephyr/drivers/adc.h>
+
 /* This structure enforces the header file is included only once in the build.
  * Violating this requirement triggers a multiple definition error at link time.
  */
 const struct {} battery_def_include_once;
 
-#define BATTERY_MEAS_ADC_INPUT		NRF_SAADC_INPUT_AIN3
+#define BATTERY_MEAS_ADC_INPUT		NRFX_ANALOG_EXTERNAL_AIN3
 #define BATTERY_MEAS_ADC_GAIN		ADC_GAIN_1
 #define BATTERY_MEAS_VOLTAGE_GAIN	1
 

applications/nrf_desktop/configuration/nrf52dmouse_nrf52832/battery_def.h

@@ -8,12 +8,15 @@
  * module and holds information about battery characteristic.
  */
 
+#include <helpers/nrfx_analog_common.h>
+#include <zephyr/drivers/adc.h>
+
 /* This structure enforces the header file is included only once in the build.
  * Violating this requirement triggers a multiple definition error at link time.
  */
 const struct {} battery_def_include_once;
 
-#define BATTERY_MEAS_ADC_INPUT		NRF_SAADC_INPUT_AIN2
+#define BATTERY_MEAS_ADC_INPUT		NRFX_ANALOG_EXTERNAL_AIN2
 #define BATTERY_MEAS_ADC_GAIN		ADC_GAIN_1_4
 #define BATTERY_MEAS_VOLTAGE_GAIN	4
 

applications/nrf_desktop/configuration/nrf52kbd_nrf52832/battery_def.h

@@ -8,12 +8,15 @@
  * module and holds information about battery characteristic.
  */
 
+#include <helpers/nrfx_analog_common.h>
+#include <zephyr/drivers/adc.h>
+
 /* This structure enforces the header file is included only once in the build.
  * Violating this requirement triggers a multiple definition error at link time.
  */
 const struct {} battery_def_include_once;
 
-#define BATTERY_MEAS_ADC_INPUT		NRF_SAADC_INPUT_VDD
+#define BATTERY_MEAS_ADC_INPUT		NRFX_ANALOG_INTERNAL_VDD
 #define BATTERY_MEAS_ADC_GAIN		ADC_GAIN_1_6
 #define BATTERY_MEAS_VOLTAGE_GAIN	6