pinctrl: rockchip: Parse pin groups before calling pinctrl_register()

Just like in (529301c1 pinctrl: samsung: Parse pin groups before
calling pinctrl_register()), Rockchip also needs to parse pin groups
earlier to make hogs work.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Tested-by: Chris Zhong <zyw@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>