pinctrl: vt8500: correct wrong offset in bank 10 of newer chips

triple-commit since vtwm-testing and vtwm-smp appears to be
dead-end branches.
devicetree: wm8880: Change wm8880.dtsi to reflect new UART
which is already commited

Signed-off-by: Helmut Stengele <lautriv@coldplug.net>
pinctrl: vt8500: Separate the pinctrl for wm8880 from 8850
for further testing, applied it's own file and changed devicetree.

Signed-off-by: Helmut Stengele <lautriv@coldplug.net>