ARM: dts: dra7-l4: mark timer13-16 as pwm capable

DMTimers 13 - 16 are PWM capable and also can be used for CPTS input
signals generation. Hence, mark them as "ti,timer-pwm".
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/dra7-l4.dtsi

@@ -3474,6 +3474,7 @@ timer13: timer@0 {
 				clocks = <&l4per3_clkctrl DRA7_L4PER3_TIMER13_CLKCTRL 24>;
 				clock-names = "fck";
 				interrupts = <GIC_SPI 339 IRQ_TYPE_LEVEL_HIGH>;
+				ti,timer-pwm;
 			};
 		};
 
@@ -3501,6 +3502,7 @@ timer14: timer@0 {
 				clocks = <&l4per3_clkctrl DRA7_L4PER3_TIMER14_CLKCTRL 24>;
 				clock-names = "fck";
 				interrupts = <GIC_SPI 340 IRQ_TYPE_LEVEL_HIGH>;
+				ti,timer-pwm;
 			};
 		};
 
@@ -3528,6 +3530,7 @@ timer15: timer@0 {
 				clocks = <&l4per3_clkctrl DRA7_L4PER3_TIMER15_CLKCTRL 24>;
 				clock-names = "fck";
 				interrupts = <GIC_SPI 341 IRQ_TYPE_LEVEL_HIGH>;
+				ti,timer-pwm;
 			};
 		};
 
@@ -3555,6 +3558,7 @@ timer16: timer@0 {
 				clocks = <&l4per3_clkctrl DRA7_L4PER3_TIMER16_CLKCTRL 24>;
 				clock-names = "fck";
 				interrupts = <GIC_SPI 342 IRQ_TYPE_LEVEL_HIGH>;
+				ti,timer-pwm;
 			};
 		};