dt-bindings: timer: nuvoton: Clarify that interrupt of timer 0 should be specified

The NPCM750 Timer/Watchdog Controller has multiple interrupt lines,
connected to multiple timers. The driver uses timer 0 for timer
interrupts, so the interrupt line corresponding to timer 0 should be
specified in DT.

I removed the mention of "flags for falling edge", because the timer
controller uses high-level interrupts rather than falling-edge
interrupts, and whether flags should be specified is up the interrupt
controller's DT binding.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210108163004.492649-1-j.neuschaefer@gmx.net

Documentation/devicetree/bindings/timer/nuvoton,npcm7xx-timer.txt

@@ -6,8 +6,7 @@ timer counters.
 Required properties:
 - compatible      : "nuvoton,npcm750-timer" for Poleg NPCM750.
 - reg             : Offset and length of the register set for the device.
-- interrupts      : Contain the timer interrupt with flags for
-                    falling edge.
+- interrupts      : Contain the timer interrupt of timer 0.
 - clocks          : phandle of timer reference clock (usually a 25 MHz clock).
 
 Example: