[ARM] 5457/1: mach-imx gpio buildfix

From: David Brownell <dbrownell@users.sourceforge.net>

Fix GPIO-related build error on mach-imx platform:

  CC      drivers/spi/spi_gpio.o
In file included from /home/db/kernel/scratch/arch/arm/include/asm/gpio.h:5,
                 from include/linux/gpio.h:7,
                 from drivers/spi/spi_gpio.c:23:
arch/arm/mach-imx/include/mach/gpio.h: In function 'imx_gpio_get_value':
arch/arm/mach-imx/include/mach/gpio.h:27: error: implicit declaration of function '__REG2'
arch/arm/mach-imx/include/mach/gpio.h:27: error: 'IMX_IO_BASE' undeclared (first use in this function)
arch/arm/mach-imx/include/mach/gpio.h:27: error: (Each undeclared identifier is reported only once
arch/arm/mach-imx/include/mach/gpio.h:27: error: for each function it appears in.)
arch/arm/mach-imx/include/mach/gpio.h: In function 'imx_gpio_set_value_inline':
arch/arm/mach-imx/include/mach/gpio.h:36: error: 'IMX_IO_BASE' undeclared (first use in this function)
arch/arm/mach-imx/include/mach/gpio.h:36: error: lvalue required as left operand of assignment
arch/arm/mach-imx/include/mach/gpio.h:38: error: lvalue required as left operand of assignment
	...
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-imx/include/mach/gpio.h

 #ifndef _IMX_GPIO_H
 
 #include <linux/kernel.h>
+#include <mach/hardware.h>
 #include <mach/imx-regs.h>
 
 #define IMX_GPIO_ALLOC_MODE_NORMAL	0