ARM: dts: gemini: add pin control set-up for the SoC

This adds the basic pin control muliplexing settings for the
Gemini SoC: parallel (NOR) flash, SATA, optional IDE, PCI and
UART.

We also select the right GPIO groups on all applicable systems
so that GPIO keys/LEDs work smoothly.

We can then build upon this for more complex systems.

Acked-by: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>