ARM: at91/dt: sam9261: correctly define mainck

mainck (CKGR_MCFR register) is actually using main_osc (CKGR_MOR register).
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

arch/arm/boot/dts/at91sam9261.dtsi

@@ -581,13 +581,19 @@ clk32k: slck {
 					clocks = <&slow_rc_osc &slow_xtal>;
 				};
 
-				main: mainck {
-					compatible = "atmel,at91rm9200-clk-main";
+				main_osc: main_osc {
+					compatible = "atmel,at91rm9200-clk-main-osc";
 					#clock-cells = <0>;
 					interrupts-extended = <&pmc AT91_PMC_MOSCS>;
 					clocks = <&main_xtal>;
 				};
 
+				main: mainck {
+					compatible = "atmel,at91rm9200-clk-main";
+					#clock-cells = <0>;
+					clocks = <&main_osc>;
+				};
+
 				plla: pllack {
 					compatible = "atmel,at91rm9200-clk-pll";
 					#clock-cells = <0>;