Fix memory leaks in cmdInterfaceEdit and cmdNWFilterEdit.

This applies a fix to thos functions similar to that made to cmdEdit
in 27089506, thus fnixing a memory
leak - if tmp is unlinked and NULLed early in the function, the memory
used by tmp is never freed. Since we will always unlink tmp prior to
freeing its memory at the end of the function, just remove the earlier
code and let cleanup: do the cleanup.

tools/virsh.c

@@ -3248,9 +3248,6 @@ cmdInterfaceEdit (vshControl *ctl, const vshCmd *cmd)
     doc_edited = editReadBackFile (ctl, tmp);
     if (!doc_edited) goto cleanup;
 
-    unlink (tmp);
-    tmp = NULL;
-
     /* Compare original XML with edited.  Has it changed at all? */
     if (STREQ (doc, doc_edited)) {
         vshPrint (ctl, _("Interface %s XML configuration not changed.\n"),
@@ -4193,9 +4190,6 @@ cmdNWFilterEdit (vshControl *ctl, const vshCmd *cmd)
     doc_edited = editReadBackFile (ctl, tmp);
     if (!doc_edited) goto cleanup;
 
-    unlink (tmp);
-    tmp = NULL;
-
     /* Compare original XML with edited.  Has it changed at all? */
     if (STREQ (doc, doc_edited)) {
         vshPrint (ctl, _("Network filter %s XML configuration not changed.\n"),