[ARM] Orion: clean up addr-map.c after window setting code purge

This patch cleans up Orion's addr-map.c a bit after all peripheral
window programming code has been moved out into the relevant drivers.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Reviewed-by: Tzachi Perelstein <tzachi@marvell.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@marvell.com>