Allocate some memories in SPIRAM first.

Try to allocate some WiFi and LWIP memories in SPIRAM first. If
    failed, try to allocate in internal RAM then.

components/esp32/include/esp_wifi_internal.h

@@ -121,6 +121,41 @@ esp_err_t esp_wifi_internal_reg_rxcb(wifi_interface_t ifx, wifi_rxcb_t fn);
   */
 esp_err_t esp_wifi_internal_set_sta_ip(void);
 
+/**
+  * @brief     Allocate a chunk of memory for WiFi driver
+  *
+  * @attention This API is not used for DMA memory allocation.
+  *
+  * @param     size_t size : Size, in bytes, of the amount of memory to allocate
+  *
+  * @return    A pointer to the memory allocated on success, NULL on failure
+  */
+void *wifi_malloc( size_t size );
+
+/**
+  * @brief     Reallocate a chunk of memory for WiFi driver
+  *
+  * @attention This API is not used for DMA memory allocation.
+  *
+  * @param     void * ptr  : Pointer to previously allocated memory, or NULL for a new allocation.
+  * @param     size_t size : Size, in bytes, of the amount of memory to allocate
+  *
+  * @return    A pointer to the memory allocated on success, NULL on failure
+  */
+void *wifi_realloc( void *ptr, size_t size );
+
+/**
+  * @brief     Callocate memory for WiFi driver
+  *
+  * @attention This API is not used for DMA memory allocation.
+  *
+  * @param     size_t n    : Number of continuing chunks of memory to allocate
+  * @param     size_t size : Size, in bytes, of the amount of memory to allocate
+  *
+  * @return    A pointer to the memory allocated on success, NULL on failure
+  */
+void *wifi_calloc( size_t n, size_t size );
+
 #ifdef __cplusplus
 }
 #endif