ARM: dts: STiH407-pinctrl: Add Pinctrl group for HW flow-control

Each serial port which supports HW flow-control should have 2 Pinctrl
groups.  One for when HW flow-control is in progress, where the IP
will take over controlling the lines and another group which enables
the lines to be toggled using GPIO mechanisms.
Acked-by: NPeter Griffin <peter.griffin@linaro.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm/boot/dts/stih407-pinctrl.dtsi

@@ -465,8 +465,16 @@
 			serial0 {
 				pinctrl_serial0: serial0-0 {
 					st,pins {
-						tx = <&pio17 0 ALT1 OUT>;
-						rx = <&pio17 1 ALT1 IN>;
+						tx =  <&pio17 0 ALT1 OUT>;
+						rx =  <&pio17 1 ALT1 IN>;
+					};
+				};
+				pinctrl_serial0_hw_flowctrl: serial0-0_hw_flowctrl {
+					st,pins {
+						tx =  <&pio17 0 ALT1 OUT>;
+						rx =  <&pio17 1 ALT1 IN>;
+						cts = <&pio17 2 ALT1 IN>;
+						rts = <&pio17 3 ALT1 OUT>;
 					};
 				};
 			};