soc: fix CPU frequency not updated in rtc_clk_init

Add missing call to rtc_clk_cpu_freq_set_config

Merges https://github.com/espressif/esp-idf/pull/2398

components/soc/esp32/rtc_clk_init.c

@@ -119,6 +119,7 @@ void rtc_clk_init(rtc_clk_config_t cfg)
 
     bool res = rtc_clk_cpu_freq_mhz_to_config(cfg.cpu_freq_mhz, &new_config);
     assert(res && "invalid CPU frequency value");
+    rtc_clk_cpu_freq_set_config(&new_config);
 
     /* Configure REF_TICK */
     REG_WRITE(APB_CTRL_XTAL_TICK_CONF_REG, xtal_freq - 1);