The pinmux command uses functions pinctrl_get_pin_*(), which are missing
if PINCTRL config option is disabled.
Signed-off-by: Marek Behún <marek.behun@nic.cz> Cc: Simon Glass <sjg@chromium.org> Cc: Tom Rini <trini@konsulko.com> Reviewed-by: Simon Glass <sjg@chromium.org>