of: selftest: add deferred probe interrupt test

Signed-off-by: Rob Herring <robh@kernel.org>
[grant.likely: fixed failure when root node specifies the interrupt parent]
Signed-off-by: Grant Likely <grant.likely@linaro.org>

drivers/of/testcase-data/tests-interrupts.dtsi

@@ -54,5 +54,18 @@
 						      <&test_intmap1 1 2>;
 			};
 		};
+
+		testcase-device1 {
+			compatible = "testcase-device";
+			interrupt-parent = <&test_intc0>;
+			interrupts = <1>;
+		};
+
+		testcase-device2 {
+			compatible = "testcase-device";
+			interrupt-parent = <&test_intc2>;
+			interrupts = <1>; /* invalid specifier - too short */
+		};
 	};
+
 };