CLEANUP: mux-h2: Rename h2s_frt_make_resp_data() to be generic

h2s_frt_make_resp_data() is now used to emit DATA frames on the frontend and
the backend side. Thus it is renamed into h2s_make_data().
diff --git a/src/mux_h2.c b/src/mux_h2.c
index b90c0a1..762e99e 100644
--- a/src/mux_h2.c
+++ b/src/mux_h2.c
@@ -5400,7 +5400,7 @@
  * happened subsequently to a successful send. Returns the number of data bytes
  * consumed, or zero if nothing done. Note that EOM count for 1 byte.
  */
-static size_t h2s_frt_make_resp_data(struct h2s *h2s, struct buffer *buf, size_t count)
+static size_t h2s_make_data(struct h2s *h2s, struct buffer *buf, size_t count)
 {
 	struct h2c *h2c = h2s->h2c;
 	struct htx *htx;
@@ -6108,7 +6108,7 @@
 				 * This EOM necessarily is one before trailers, as the EOM following
 				 * trailers would have been consumed by the trailers parser.
 				 */
-				ret = h2s_frt_make_resp_data(h2s, buf, count);
+				ret = h2s_make_data(h2s, buf, count);
 				if (ret > 0) {
 					htx = htx_from_buf(buf);
 					total += ret;