goldfish: fix sparse warnings

drivers/tty/goldfish.c:160:46: warning: Using plain integer as NULL pointer
drivers/tty/goldfish.c:320:22: warning: Using plain integer as NULL pointer

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/goldfish.c

@@ -157,7 +157,7 @@ static int goldfish_tty_console_setup(struct console *co, char *options)
 {
 	if ((unsigned)co->index > goldfish_tty_line_count)
 		return -ENODEV;
-	if (goldfish_ttys[co->index].base == 0)
+	if (!goldfish_ttys[co->index].base)
 		return -ENODEV;
 	return 0;
 }
@@ -317,7 +317,7 @@ static int goldfish_tty_remove(struct platform_device *pdev)
 	unregister_console(&qtty->console);
 	tty_unregister_device(goldfish_tty_driver, pdev->id);
 	iounmap(qtty->base);
-	qtty->base = 0;
+	qtty->base = NULL;
 	free_irq(qtty->irq, pdev);
 	goldfish_tty_current_line_count--;
 	if (goldfish_tty_current_line_count == 0)