core: main: Dont check for serialEventRun as its always defined

Signed-off-by: Dakkshesh <dakkshesh5@gmail.com>

Author: beakthoven

cores/arduino/main.cpp

@@ -44,7 +44,7 @@ int main(void)
 
 	for (;;) {
 		loop();
-		if (serialEventRun) serialEventRun();
+		serialEventRun();
 	}
 
 	return 0;