flex requires GNU make

flex/flex.spec

@@ -58,7 +58,7 @@ Source0:      http://astro.temple.edu/~john43/flex/flex-%{V_devel_maj}-developer
 #   build information
 Prefix:       %{l_prefix}
 BuildRoot:    %{l_buildroot}
-BuildPreReq:  OpenPKG, openpkg >= 0.9-20011025.0, bison
+BuildPreReq:  OpenPKG, openpkg >= 0.9-20011025.0, bison, make
 PreReq:       OpenPKG, openpkg >= 0.9-20011025.0
 AutoReq:      no
 AutoReqProv:  no