usb: gadget: fix pxa25x compilation problems

In commit
88f718e3
"ARM: pxa: delete the custom GPIO header"
we removed the implicit inclusion of <mach/gpio.h>
from <linux/gpio.h>.

The pxa25x_udc was not using that, but it was relying
on <linux/gpio.h> to implictly include <mach/gpio.h>
which in turn implicitly included <mach/hardware.h>,
which was needed for the driver to compile.

Fix this up by explicitly including the necessary
<mach/hardware.h> header.
Reported-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/pxa25x_udc.c

@@ -54,6 +54,7 @@
  */
 #ifdef CONFIG_ARCH_PXA
 #include <mach/pxa25x-udc.h>
+#include <mach/hardware.h>
 #endif
 
 #ifdef CONFIG_ARCH_LUBBOCK