[ARM] 4141/1: consolidate functions that handles gpio in pxa2xx_udc

This patch renames pxa_gpio_set/get functions defined in drivers/usb/gadget/pxa2xx_udc.h to udc_gpio_set/get.

These functions are moved from drivers/usb/gadget/pxa2xx_udc.h to include/asm-arm/arch-pxa2xx/udc.h

Creates new functions: udc_gpio_to_irq, udc_gpio_init_vbus, udc_gpio_init_pullup in include/asm-arm/arch-pxa2xx/udc.h. These functions are used in drivers/usb/gadget/pxa2xx_udc.c instead of direct low-level (pxa2xx only) functions.

Creates all these udc_gpio_* functions in include/asm-arm/arch-ixp4xx/udc.h. This implementation has no real code because ixp4xx doesn't use vbus - only vbus uses all these gpio functions (and because ixp4xx misses any function which converts number of gpio pin into it's irq).

This is next step to make pxa2xx_udc fully work on ixp4xx platform.

Signed-off-by: Milan Svoboda <msvoboda@ra.rockwell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>