ospfd: remove unused code

The code for nssa_range and other bits that were written but
never used.
diff --git a/ospfd/ospf_vty.c b/ospfd/ospf_vty.c
index b1526c3..577e417 100644
--- a/ospfd/ospf_vty.c
+++ b/ospfd/ospf_vty.c
@@ -3732,7 +3732,7 @@
   return 0;
 }
 
-/* N.B. This function currently seems to be unused. */
+#if 0
 static int
 show_as_external_lsa_stdvty (struct ospf_lsa *lsa)
 {
@@ -3756,6 +3756,7 @@
 
   return 0;
 }
+#endif
 
 /* Show AS-NSSA-LSA detail information. */
 static int