pinctrl: meson-gxbb: add missing GPIOX_22 pin

GPIOX_22 is declared as a gpio but the id is no present in the pin
table. This hole trigger an error while reading the pingroup debugfs entry

GPIOX_22 is no routed externally. For all we know, it could an internal
pin of SoC

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/meson/pinctrl-meson-gxbb.c

@@ -136,6 +136,7 @@ static const struct pinctrl_pin_desc meson_gxbb_periphs_pins[] = {
 	MESON_PIN(GPIOX_19),
 	MESON_PIN(GPIOX_20),
 	MESON_PIN(GPIOX_21),
+	MESON_PIN(GPIOX_22),
 
 	MESON_PIN(GPIOCLK_0),
 	MESON_PIN(GPIOCLK_1),