ARM: plat-iop: instantiate GPIO from platform device

This converts the IOP32x and IOP33x platforms to pass their
base address offset by a resource attached to a platform device
instead of using static offset macros implicitly passed
through <linux/gpio.h> including <mach/gpio.h>. Delete the
local <mach/gpio.h> and <asm/hardware/iop3xx-gpio.h> headers
and remove the selection of NEED_MACH_GPIO_H.

Pass the virtual address as a resource in the platform device
at this point for bisectability, next patch will pass the
physical address as is custom.

Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Mikael Pettersson <mikpe@it.uu.se>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/arch/arm/mach-iop32x/n2100.c b/arch/arm/mach-iop32x/n2100.c
index bc40a97..c1cd80e 100644
--- a/arch/arm/mach-iop32x/n2100.c
+++ b/arch/arm/mach-iop32x/n2100.c
@@ -41,6 +41,7 @@
 #include <asm/page.h>
 #include <asm/pgtable.h>
 #include <mach/time.h>
+#include "gpio-iop32x.h"
 
 /*
  * N2100 timer tick configuration.
@@ -345,6 +346,7 @@
 
 static void __init n2100_init_machine(void)
 {
+	register_iop32x_gpio();
 	platform_device_register(&iop3xx_i2c0_device);
 	platform_device_register(&n2100_flash_device);
 	platform_device_register(&n2100_serial_device);