Make nsgmls compile on OpenBSD.

As far as I can tell, the duplicate instantiations from entmgr_inst.m4 are
unnecessary and only cause compile failures without -fpermissive.

cde/programs/nsgmls/CmdLineApp.C

@@ -58,7 +58,7 @@
 
 #include "ConsoleOutput.h"
 
-#if defined(linux)
+#if defined(linux) || defined(CSRG_BASED)
 #include <iostream>
 #include <fstream>
 using namespace std;
@@ -292,7 +292,7 @@ Boolean CmdLineApp::openFilebufWrite(filebuf &file,
     return 0;
   return file.attach(fd) != 0;
 #else
-#if defined(linux)
+#if defined(linux) || defined(CSRG_BASED)
   return file.open(filename, ios::out|ios::trunc) != 0;
 #else
   return file.open(filename, ios::out|ios::trunc|IOS_BINARY) != 0;