pinctrl: renesas: rzg2l: Return -EINVAL for pins which have input disabled

Pin status reported by pinconf-pins file always reported pin status as
"input enabled" even for pins which had input disabled. Fix this by
returning -EINVAL for the pins which have input disabled.

Fixes: c4c4637e ("pinctrl: renesas: Add RZ/G2L pin and gpio controller driver")
Reported-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Phil Edworthy <phil.edworthy@renesas.com>
Link: https://lore.kernel.org/r/20220511094057.3151-1-prabhakar.mahadev-lad.rj@bp.renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

drivers/pinctrl/renesas/pinctrl-rzg2l.c

@@ -517,6 +517,8 @@ static int rzg2l_pinctrl_pinconf_get(struct pinctrl_dev *pctldev,
 		if (!(cfg & PIN_CFG_IEN))
 			return -EINVAL;
 		arg = rzg2l_read_pin_config(pctrl, IEN(port_offset), bit, IEN_MASK);
+		if (!arg)
+			return -EINVAL;
 		break;
 
 	case PIN_CONFIG_POWER_SOURCE: {