ARM: dts: STi: Fix pinconf setup for STiH416 serial2

This patch fixes a bug in pinctrl setup of serial2 device, Some of the
pins in the pinctrl node of serial2 do not belong to that
pin-controller. This patch divides them in the pins into there
respective pin controller nodes.

Without this patch serial on StiH416-B2000 Board will not work as it
fails with:

"st-pinctrl pin-controller-rear.3: failed to get pin(99) name
st-pinctrl pin-controller-rear.3: maps: function serial2 group serial2-0
num 4
pinconfig core: failed to register map default (3): no group/pin given"
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/boot/dts/stih416-pinctrl.dtsi

@@ -166,6 +166,15 @@ PIO31: gpio@fee09000 {
 				reg		= <0x9000 0x100>;
 				st,bank-name	= "PIO31";
 			};
+
+			serial2-oe {
+				pinctrl_serial2_oe: serial2-1 {
+					st,pins {
+						output-enable	= <&PIO11 3 ALT2 OUT>;
+					};
+				};
+			};
+
 		};
 
 		pin-controller-rear {
@@ -218,7 +227,6 @@ pinctrl_serial2: serial2-0 {
 					st,pins {
 						tx	= <&PIO17 4 ALT2 OUT>;
 						rx	= <&PIO17 5 ALT2 IN>;
-						output-enable	= <&PIO11 3 ALT2 OUT>;
 					};
 				};
 			};

arch/arm/boot/dts/stih416.dtsi

@@ -79,7 +79,7 @@ serial2: serial@fed32000{
 			interrupts	= <0 197 0>;
 			clocks          = <&CLK_S_ICN_REG_0>;
 			pinctrl-names 	= "default";
-			pinctrl-0 	= <&pinctrl_serial2>;
+			pinctrl-0 	= <&pinctrl_serial2 &pinctrl_serial2_oe>;
 		};
 
 		/* SBC_UART1 */