canbusload: flush output at the end of each cycle

When canbusload is piped to another program, the output
is queued for several cycles. This patch will flush the output
explicitely.

Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be>

canbusload.c

@@ -201,6 +201,7 @@ void printstats(int signo)
 	}
 
 	printf("\n");
+	fflush(stdout);
 
 	alarm(1);
 }