pinctrl: k210: Fix bias-pull-up

Using bias-pull-up would actually cause the pin to have its pull-down
enabled. Fix this.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Fixes: d4c34d09 ("pinctrl: Add RISC-V Canaan Kendryte K210 FPIOA driver")
Link: https://lore.kernel.org/r/20220209182822.640905-1-seanga2@gmail.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>