samples: hello arduino: Clean up

samples/hello_arduino/src/app.cpp

@@ -3,27 +3,13 @@
  */
 
 #include <Arduino.h>
-#include "zephyrSerial.h"
-
 
 void setup() {
-  // put your setup code here, to run once:
-  Serial.begin(115200); // dummy as of now, need to study and refer https://docs.zephyrproject.org/latest/hardware/peripherals/uart.html
+	// put your setup code here, to run once:
+	Serial.begin(115200);
 }
 void loop() {
-  char c = 'D';
-  size_t ret1;
-  size_t ret2;
-  ret1 = Serial.print(c);
-  ret2 = Serial.println("Hello, World!");
-  printk("Sizes: %d %d\n", ret1, ret2);
-  Serial.println();
-  ret1 = Serial.print("My letter is: ");
-  ret2 = Serial.println(c);
-  printk("Sizes: %d %d\n", ret1, ret2);
-  Serial.println();
-  char myString[] = "Will it print?";
-  ret1 = Serial.println(myString);
-  printk("Size: %d \n\n\n", ret1);
-  delay(1000); // 1 second delay
+	// loop function for continuously executing code
+	Serial.println("Hello World!");
+	delay(1000);
 }