dt-bindings: vcpu_stall_detector: Add a PPI interrupt to the virtual device

The vcpu stall detector allows the host to monitor the availability of a
guest VM. Introduce a PPI interrupt which can be injected from the host
into the virtual gic to let the guest reboot itself.

Acked-by: Conor Dooley <[e-mail]>
Signed-off-by: Sebastian Ene <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Documentation/devicetree/bindings/misc/qemu,vcpu-stall-detector.yaml

···
       Defaults to 10 if unset.
     default: 10
 
+  interrupts:
+    maxItems: 1
+
   timeout-sec:
     description: |
       The stall detector expiration timeout measured in seconds.
···
 
 examples:
   - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
     vmwdt@9030000 {
       compatible = "qemu,vcpu-stall-detector";
       reg = <0x9030000 0x10000>;
       clock-frequency = <10>;
       timeout-sec = <8>;
+      interrupts = <GIC_PPI 15 IRQ_TYPE_EDGE_RISING>;
     };