ARM: ux500: switch to using pinctrl for uart0

UART0 had a hack that enabled its pins on init and put it to
sleep on the exit callback. Replace this with the pinctrl calls
to do the same thing and update the runtime table with the two
apropriate states for runtime/active and idle.

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