correct match value for first fragments

This commit was SVN r3419.

src/mca/ptl/mx/ptl_mx.c

@@ -240,7 +240,7 @@ int mca_ptl_mx_send(
         sendfrag->frag_segments,
         sendfrag->frag_segment_count,
         ptl_peer->peer_addr,
-        1,
+        0,
         sendfrag,
         &sendfrag->frag_request);
     if(mx_return != MX_SUCCESS) {