Revert "lib: address -Wunused-but-set-variable"

Stephen Hemminger's commits contain all the changes and
several other warning fixes.

This reverts commit 6947dbebdc91b6272f8107a6e0dd211457438606.
diff --git a/lib/if_rmap.c b/lib/if_rmap.c
index b49d266..ddc62fd 100644
--- a/lib/if_rmap.c
+++ b/lib/if_rmap.c
@@ -212,6 +212,7 @@
        "Route map interface name\n")
 {
   enum if_rmap_type type;
+  struct if_rmap *if_rmap;
 
   if (strncmp (argv[1], "i", 1) == 0)
     type = IF_RMAP_IN;
@@ -223,7 +224,7 @@
       return CMD_WARNING;
     }
 
-  if_rmap_set (argv[2], type, argv[0]);
+  if_rmap = if_rmap_set (argv[2], type, argv[0]);
 
   return CMD_SUCCESS;
 }