adc: remove useless adc_ll_set_sar_clk_div in LL

components/hal/esp32c3/include/hal/adc_ll.h

@@ -651,15 +651,6 @@ static inline adc_ll_power_t adc_ll_get_power_manage(void)
     return manage;
 }
 
-/**
- * ADC SAR clock division factor setting. ADC SAR clock devided from `RTC_FAST_CLK`.
- *
- * @param div Division factor.
- */
-static inline void adc_ll_set_sar_clk_div(adc_ll_num_t adc_n, uint32_t div)
-{
-}
-
 /**
  * Set ADC module controller.
  * There are five SAR ADC controllers: