docs(i2s): Fix I2S documentation example (#9916)

* docs(i2s): Fix I2S documentation example

* docs(idf): Fix name of Arduino as component link

docs/en/advanced_utils.rst

@@ -6,6 +6,6 @@ Advanced Utilities
     :maxdepth: 2
 
     Library Builder <lib_builder>
-    ESP-IDF as Component <esp-idf_component>
+    Arduino as an ESP-IDF component <esp-idf_component>
     OTA Web Update <ota_web_update>
     makeEspArduino <make>

docs/en/api/i2s.rst

@@ -536,7 +536,7 @@ Sample code
   #include <ESP_I2S.h>
 
   const int buff_size = 128;
-  int available, read;
+  int available_bytes, read_bytes;
   uint8_t buffer[buff_size];
   I2SClass I2S;
 
@@ -544,13 +544,13 @@ Sample code
     I2S.setPins(5, 25, 26, 35, 0); //SCK, WS, SDOUT, SDIN, MCLK
     I2S.begin(I2S_MODE_STD, 16000, I2S_DATA_BIT_WIDTH_16BIT, I2S_SLOT_MODE_STEREO);
     I2S.read();
-    available = I2S.available();
-    if(available < buff_size) {
-      read = I2S.read(buffer, available);
+    available_bytes = I2S.available();
+    if(available_bytes < buff_size) {
+      read_bytes = I2S.read(buffer, available_bytes);
     } else {
-      read = I2S.read(buffer, buff_size);
+      read_bytes = I2S.read(buffer, buff_size);
     }
-    I2S.write(buffer, read);
+    I2S.write(buffer, read_bytes);
     I2S.end();
   }