[nrf fromlist] drivers: adc: nrfx: Temporary fix for SAADC power consumption

This is temporary fix for SAADC power consumption. Need to be
removed after hal_nrfx version upgrade.

Upstream PR #: 94383

Signed-off-by: Jakub Zymelka <[email protected]>
(cherry picked from commit 2158e6b)

Author: jaz1-nordic

drivers/adc/adc_nrfx_saadc.c

@@ -755,6 +755,7 @@ static void event_handler(const nrfx_saadc_evt_t *event)
 			correct_single_ended(&m_data.ctx.sequence, m_data.user_buffer,
 					     event->data.done.size);
 		}
+		nrfy_saadc_disable(NRF_SAADC);
 		adc_context_on_sampling_done(&m_data.ctx, DEVICE_DT_INST_GET(0));
 	} else if (event->type == NRFX_SAADC_EVT_CALIBRATEDONE) {
 		err = nrfx_saadc_mode_trigger();