ARM: tegra: use fixed PCI i/o mapping

Move tegra PCI to fixed i/o mapping and remove io.h.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
Acked-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>