Rather than having a single tegra-pinctrl driver that determines whether
it's running on Tegra20 or Tegra30, instead have separate drivers for
each that call into utility functions to implement the majority of the
driver. This change is based on review feedback of the SPEAr pinctrl
driver, which had originally copied to Tegra driver structure.

This requires that the two drivers have unique names. Update a couple
spots in arch/arm/mach-tegra for the name change.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>

This adds a driver for the Tegra pinmux, and required parameterization
data for Tegra20 and Tegra30.

The driver is initially added with driver name and device tree compatible
value that won't cause this driver to be used. A later change will switch
the pinctrl driver to use the correct values, switch the old pinmux
driver to be disabled, and update all code that uses the old pinmux APIs
to use the new pinctrl APIs.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Olof Johansson <olof@lixom.net>
[squashed "fix case of Tegra30's foo_groups[] arrays"]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>