pinctrl: uniphier: support per-pin input enable for new SoCs

Upcoming new pinctrl drivers for PH1-LD11 and PH-LD20 support input
signal gating for each pin.  (While, existing ones only support it
per pin-group.)  This commit prepares the core part for that.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/drivers/pinctrl/uniphier/pinctrl-uniphier.h b/drivers/pinctrl/uniphier/pinctrl-uniphier.h
index d582317..2b43848 100644
--- a/drivers/pinctrl/uniphier/pinctrl-uniphier.h
+++ b/drivers/pinctrl/uniphier/pinctrl-uniphier.h
@@ -70,6 +70,7 @@
 	const char * const *functions;
 	int functions_count;
 	unsigned caps;
+#define UNIPHIER_PINCTRL_CAPS_PERPIN_IECTRL	BIT(1)
 #define UNIPHIER_PINCTRL_CAPS_DBGMUX_SEPARATE	BIT(0)
 };