Secure Boot: Fixes the cpp macro in esp32 secure boot rom functions.

Closes https://github.com/espressif/esp-idf/issues/5878

components/esp_rom/include/esp32/rom/secure_boot.h

@@ -111,4 +111,8 @@ bool ets_use_secure_boot_v2(void);
 
 #endif /* CONFIG_ESP32_REV_MIN_3 */
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* _ROM_SECURE_BOOT_H_ */