BUILD: proto_uxst: do not set unused flag

Similarly to previous patch for sockpair, UNIX sockets set the
CONNECT_HAS_DATA flag without using it later, we can drop it.

(cherry picked from commit b5d1141305423bf221b554bd1349b90259afc3d7)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/src/proto_uxst.c b/src/proto_uxst.c
index 02d7069..621eb39 100644
--- a/src/proto_uxst.c
+++ b/src/proto_uxst.c
@@ -285,10 +285,6 @@
 		return SF_ERR_INTERNAL;
 	}
 
-	/* if a send_proxy is there, there are data */
-	if (conn->send_proxy_ofs)
-		flags |= CONNECT_HAS_DATA;
-
 	if (global.tune.server_sndbuf)
                 setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &global.tune.server_sndbuf, sizeof(global.tune.server_sndbuf));