ARM: sa11x0: fix collie build error

f408c985 (GPIO: sa1100: implement proper gpiolib gpio_to_irq conversion)
made gpio_to_irq() a function.  This breaks collie where it's used to
initialize some static data.  Fix that by moving the initialization to
the init code.

arch/arm/mach-sa1100/collie.c:139: error: initializer element is not constant
arch/arm/mach-sa1100/collie.c:139: error: (near initialization for 'collie_power_resource[0].start')
arch/arm/mach-sa1100/collie.c:140: error: initializer element is not constant
arch/arm/mach-sa1100/collie.c:140: error: (near initialization for 'collie_power_resource[0].end')

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>