Add test file for issue-134-specific tests

New file t/tree/issue134.c exercises the bugs noted in
<https://github.com/bootlin/elixir/issues/134#issue-624392766>.
I did not copy in the files listed in that comment because those files
are GPL-2.0-only or an unspecified GPL license, not GPL-2.0-or-later.

t/tree/issue134.c

@@ -0,0 +1,49 @@
+/*
+ * issue134.c: tests exhibiting problems noted in
+ * https://github.com/bootlin/elixir/issues/134#issue-624392766
+ *
+ * t/tree/issue134.c
+ * SPDX-License-Identifier: CC0-1.0
+ */
+
+/**
+ * issue134_function1:
+ *	Do something magical
+ *	and something quotidian
+ *
+ * @p1: Param
+ *
+ * Do something
+ *
+ * Returns whatever
+ */
+int issue134_function1(int p1)
+{
+    write_test_cases();
+}
+
+/**
+ * issue134_function2: - does what it does
+ * @param:  something
+ *
+ * Whatever
+ *
+ * Whatever, paragraph 2.
+ */
+void __sched issue134_function2(struct completion *x)
+{
+	take_action();
+}
+
+/**
+ * issue134_function3() - something
+ * @param: whatever
+ * @paramii: whatever else
+ *
+ * Description
+ *
+ * Return: %magic or
+ *	   %-EIEIO if the farm bought
+ */
+int issue134_function3(struct issue134_struct1 *param,
+			       struct issue134_struct2 *paramii);