pinctrl: exynos: Add BUS1 pin controller for exynos7

USB and Power regulator on Exynos7 require gpios available
in BUS1 pin controller block.
So adding the BUS1 pinctrl support.

Signed-off-by: Naveen Krishna Ch <naveenkrishna.ch@gmail.com>
Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Acked-by: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>