runtime.Rethrow fix; llgo/ssa: IndirectJump fix

cl/_testgo/defer3/in.go

@@ -0,0 +1,23 @@
+package main
+
+func f(s string) bool {
+	return len(s) > 2
+}
+
+func fail() {
+	defer println("bye")
+	panic("panic message")
+}
+
+func main() {
+	defer func() {
+		println("hi")
+	}()
+	if s := "hello"; f(s) {
+		defer println(s)
+	} else {
+		defer println("world")
+		return
+	}
+	fail()
+}