The MPP19 and MMP20 pins also have the ability to be muxed to the uart1
function.
Add this case to the pinctrl driver.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Acked-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>