pinctrl: uniphier: support 4bit-width pin-mux register capability

On LD4 SoC or later, the pin-mux registers are 8bit wide, while 4bit
wide on sLD3 SoC.  Support it for the sLD3 pinctrl driver.

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 76ea1be..5c3db2a 100644
--- a/drivers/pinctrl/uniphier/pinctrl-uniphier.h
+++ b/drivers/pinctrl/uniphier/pinctrl-uniphier.h
@@ -67,8 +67,9 @@
 	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)
+#define UNIPHIER_PINCTRL_CAPS_PERPIN_IECTRL	BIT(2)
+#define UNIPHIER_PINCTRL_CAPS_DBGMUX_SEPARATE	BIT(1)
+#define UNIPHIER_PINCTRL_CAPS_MUX_4BIT		BIT(0)
 };
 
 #define UNIPHIER_PINCTRL_PIN(a, b)					\