pinctrl: pinctrl-zynq: Add support for 'power-source' parameter

Add support for generic pin parameter 'power-source'.
To maintain the backward compatibility, 'io-standard' parameter is still
supported in the driver.
Signed-off-by: Sai Krishna Potthuri <lakshmi.sai.krishna.potthuri@xilinx.com>
Link: https://lore.kernel.org/r/1626868353-96475-4-git-send-email-lakshmi.sai.krishna.potthuri@xilinx.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-zynq.c

@@ -1028,6 +1028,7 @@ static int zynq_pinconf_cfg_get(struct pinctrl_dev *pctldev,
 		break;
 	}
 	case PIN_CONFIG_IOSTANDARD:
+	case PIN_CONFIG_POWER_SOURCE:
 		arg = zynq_pinconf_iostd_get(reg);
 		break;
 	default:
@@ -1078,6 +1079,7 @@ static int zynq_pinconf_cfg_set(struct pinctrl_dev *pctldev,
 
 			break;
 		case PIN_CONFIG_IOSTANDARD:
+		case PIN_CONFIG_POWER_SOURCE:
 			if (arg <= zynq_iostd_min || arg >= zynq_iostd_max) {
 				dev_warn(pctldev->dev,
 					 "unsupported IO standard '%u'\n",