BUG/MEDIUM: h2: Don't forget to destroy the h2s after deferred shut.

If we had to defer shutr/shutw, and we're now done, destroy the h2s, or
nobody will do so.
diff --git a/src/mux_h2.c b/src/mux_h2.c
index d13bd95..a0357be 100644
--- a/src/mux_h2.c
+++ b/src/mux_h2.c
@@ -2997,11 +2997,20 @@
 	struct h2s *h2s = ctx;
 	long reason = (long)h2s->wait_event.handle;
 
-	if (reason & 1)
-		h2_do_shutr(h2s);
+	if (h2s->send_wait) {
+		h2s->send_wait->wait_reason &= ~SUB_CALL_UNSUBSCRIBE;
+		h2s->send_wait = NULL;
+		LIST_DEL(&h2s->list);
+		LIST_INIT(&h2s->list);
+	}
 	if (reason & 2)
 		h2_do_shutw(h2s);
+	if (reason & 1)
+		h2_do_shutr(h2s);
 
+	if (h2s->st == H2_SS_CLOSED &&
+	    !((h2s->flags & (H2_SF_BLK_MBUSY | H2_SF_BLK_MROOM | H2_SF_BLK_MFCTL))))
+		h2s_destroy(h2s);
 	return NULL;
 }