Add option to allocate external RAM using heap_alloc_caps

components/esp32/include/esp_spiram.h

@@ -39,6 +39,12 @@ esp_err_t esp_spiram_init();
 bool esp_spiram_test();
 
 
+/**
+ * @brief Add the initialized SPI RAM to the heap allocator.
+ */
+esp_err_t esp_spiram_add_to_heapalloc();
+
+
 /**
  * @brief Get the size of the attached SPI RAM chip selected in menuconfig
  *