ARM: dts: dm816x: add fck under timers1/2

Add the functional clock definition for timers1/2. This is needed so that
the clock rate claculations continue to function properly once dm816x
transitions away from hwmod data and towards the clkctrl clocks.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/dm816x.dtsi

@@ -331,6 +331,8 @@ timer1: timer@4802e000 {
 			interrupts = <67>;
 			ti,hwmods = "timer1";
 			ti,timer-alwon;
+			clocks = <&timer1_fck>;
+			clock-names = "fck";
 		};
 
 		timer2: timer@48040000 {
@@ -338,6 +340,8 @@ timer2: timer@48040000 {
 			reg = <0x48040000 0x2000>;
 			interrupts = <68>;
 			ti,hwmods = "timer2";
+			clocks = <&timer2_fck>;
+			clock-names = "fck";
 		};
 
 		timer3: timer@48042000 {