ARM: dts: am33xx: add fck under timers1/2

Add the functional clock definition for timers1/2. This is needed so that
the clock rate calculations continue to function properly once am33xx
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/am33xx.dtsi

@@ -517,6 +517,8 @@ timer1: timer@44e31000 {
 			interrupts = <67>;
 			ti,hwmods = "timer1";
 			ti,timer-alwon;
+			clocks = <&timer1_fck>;
+			clock-names = "fck";
 		};
 
 		timer2: timer@48040000 {
@@ -524,6 +526,8 @@ timer2: timer@48040000 {
 			reg = <0x48040000 0x400>;
 			interrupts = <68>;
 			ti,hwmods = "timer2";
+			clocks = <&timer2_fck>;
+			clock-names = "fck";
 		};
 
 		timer3: timer@48042000 {