MEDIUM: mux-h2: pass trailers to HTX

When receiving an H2 message in HTX mode, trailers present in chunked
messages are now properly appended to the HTX block.
diff --git a/src/mux_h2.c b/src/mux_h2.c
index 74c6c0a..e192cb3 100644
--- a/src/mux_h2.c
+++ b/src/mux_h2.c
@@ -3460,9 +3460,8 @@
 	if (htx) {
 		if (!htx_add_endof(htx, HTX_BLK_EOD))
 			goto fail;
-		/* FIXME: emit the decoded trailers here. EOM will be sent
-		 * when leaving.
-		 */
+		if (h2_make_htx_trailers(list, htx) <= 0)
+			goto fail;
 	}
 	else if (*flags & H2_SF_DATA_CHNK) {
 		/* Legacy mode with chunked encoding : we must finalize the