ARM: at91/at91sam9x5 DTS: add SCK USART pins

The SCK pins where missing in usarts pinctrl.
Signed-off-by: NRichard Genoud <richard.genoud@gmail.com>
Acked-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>

arch/arm/boot/dts/at91sam9x5.dtsi

@@ -143,6 +143,11 @@
 						atmel,pins =
 							<0 3 0x1 0x0>;	/* PA3 periph A */
 					};
+
+					pinctrl_usart0_sck: usart0_sck-0 {
+						atmel,pins =
+							<0 4 0x1 0x0>;	/* PA4 periph A */
+					};
 				};
 
 				usart1 {
@@ -161,6 +166,11 @@
 						atmel,pins =
 							<2 28 0x3 0x0>;	/* PC28 periph C */
 					};
+
+					pinctrl_usart1_sck: usart1_sck-0 {
+						atmel,pins =
+							<2 28 0x3 0x0>;	/* PC29 periph C */
+					};
 				};
 
 				usart2 {
@@ -179,6 +189,11 @@
 						atmel,pins =
 							<1 1 0x2 0x0>;	/* PB1 periph B */
 					};
+
+					pinctrl_usart2_sck: usart2_sck-0 {
+						atmel,pins =
+							<1 2 0x2 0x0>;	/* PB2 periph B */
+					};
 				};
 
 				usart3 {
@@ -197,6 +212,11 @@
 						atmel,pins =
 							<2 25 0x2 0x0>;	/* PC25 periph B */
 					};
+
+					pinctrl_usart3_sck: usart3_sck-0 {
+						atmel,pins =
+							<2 26 0x2 0x0>;	/* PC26 periph B */
+					};
 				};
 
 				uart0 {