ospfd: remove unused code

The code for nssa_range and other bits that were written but
never used.
diff --git a/ospfd/ospf_spf.c b/ospfd/ospf_spf.c
index 6dcf0b1..d7f9ba2 100644
--- a/ospfd/ospf_spf.c
+++ b/ospfd/ospf_spf.c
@@ -1042,6 +1042,7 @@
   route_table_finish (rtrs);
 }
 
+#if 0
 static void
 ospf_rtrs_print (struct route_table *rtrs)
 {
@@ -1101,6 +1102,7 @@
 
   zlog_debug ("ospf_rtrs_print() end");
 }
+#endif
 
 /* Calculating the shortest-path tree for an area. */
 static void