esp32: Use package identifier to look up SPI flash/PSRAM WP Pin, unless overridden

Allows booting in QIO/QOUT mode or with PSRAM on ESP32-PICO-V3 and
ESP32-PICO-V3-O2 without any config changes.

Custom WP pins (needed for fully custom circuit boards) should still be compatible.

components/bootloader_support/include/bootloader_flash_config.h

@@ -14,6 +14,7 @@
 
 #pragma once
 
+#include "sdkconfig.h"
 #include "esp_image_format.h"
 
 #ifdef __cplusplus
@@ -66,6 +67,22 @@ void bootloader_flash_gpio_config(const esp_image_header_t* pfhdr);
  */
 void bootloader_flash_dummy_config(const esp_image_header_t* pfhdr);
 
+#ifdef CONFIG_IDF_TARGET_ESP32
+/**
+ * @brief Return the pin number used for custom SPI flash and/or SPIRAM WP pin
+ *
+ * Can be determined by eFuse values in most cases, or overriden in configuration
+ *
+ * This value is only meaningful if the other SPI flash pins are overriden via eFuse.
+ *
+ * This value is only meaningful if flash is set to QIO or QOUT mode, or if
+ * SPIRAM is enabled.
+ *
+ * @return Pin number to use, or -1 if the default should be kept
+ */
+int bootloader_flash_get_wp_pin(void);
+#endif
+
 #ifdef __cplusplus
 }
 #endif