pinctrl: k210: Undef K210_PC_DEFAULT

pinctrl: k210: Undef K210_PC_DEFAULT

When the temporary macro K210_PC_DEFAULT is not needed anymore,
use its name in the #undef statement instead of
the incorrect "DEFAULT" name.

Fixes: d4c34d09ab03 ("pinctrl: Add RISC-V Canaan Kendryte K210 FPIOA driver")
Signed-off-by: zhang jiao <zhangjiao2@cmss.chinamobile.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/20241113071201.5440-1-zhangjiao2@cmss.chinamobile.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>