[ARM] pxa: fix tosa.c build error

Work around:
arch/arm/mach-pxa/tosa.c: In function `tosa_poweroff':
arch/arm/mach-pxa/tosa.c:470: error: `GPIO_OUT' undeclared (first use in this function)
arch/arm/mach-pxa/tosa.c:470: error: (Each undeclared identifier is reported only once
arch/arm/mach-pxa/tosa.c:470: error: for each function it appears in.)

The proper fix exists in the PXA branch of my kernel git tree, which
will be pushed during the next merge window.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-pxa/tosa.c

@@ -467,8 +467,8 @@ static struct platform_device *devices[] __initdata = {
 
 static void tosa_poweroff(void)
 {
-	pxa_gpio_mode(TOSA_GPIO_ON_RESET | GPIO_OUT);
-	GPSR(TOSA_GPIO_ON_RESET) = GPIO_bit(TOSA_GPIO_ON_RESET);
+	gpio_direction_output(TOSA_GPIO_ON_RESET, 0);
+	gpio_set_value(TOSA_GPIO_ON_RESET, 1);
 
 	mdelay(1000);
 	arm_machine_restart('h');