change(spi_flash): Flash frequency will not be decreased during DFS on ESP32-P4, when PSRAM is not enabled.

components/esp_hw_support/include/esp_private/mspi_timing_tuning.h

@@ -24,6 +24,12 @@ extern "C" {
  */
 void mspi_timing_enter_low_speed_mode(bool control_spi1);
 
+/**
+ * @brief Get PSRAM frequency in low speed mode (MHz)
+ * @return PSRAM frequency in MHz when in low speed mode
+ */
+uint32_t mspi_timing_get_psram_low_speed_freq_mhz(void);
+
 /**
  * @brief Make MSPI work under the frequency as users set, may add certain delays to MSPI RX direction to meet timing requirements.
  * @param control_spi1  Select whether to control SPI1. For tuning, we need to use SPI1. After tuning (during startup stage), let the flash driver to control SPI1
@@ -54,7 +60,6 @@ void mspi_timing_psram_tuning(void);
  */
 void mspi_timing_set_pin_drive_strength(void);
 
-
 #ifdef __cplusplus
 }
 #endif