ARM: davinci: da850: set the GPIO base to 0

ARM: davinci: da850: set the GPIO base to 0

Commit 587f7a694f01 ("gpio: davinci: Use dev name for label and
automatic base selection") broke the network support in legacy boot
mode for da850-evm since we can no longer request the MDIO clock GPIO.

We now have the option to specify the GPIO base manually for davinci,
so add the relevant fields to platform data.

Fixes: 587f7a694f01 ("gpio: davinci: Use dev name for label and automatic base selection")
Cc: stable@vger.kernel.org
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>