Resolves: #491215

Summary: mmldif crashes in PK11_CreateDigestContext
Description: NSS was not initialized.  Since cert db, key db, or secmod db are
not needed, changed to call NSS_NoDB_Init to initialize NSS.

ldap/servers/slapd/tools/mmldif.c

@@ -347,6 +347,8 @@ int mm_diff(stats_t *statsp)
     time(&statsp->diff_start_time);
     license_count = 0;
 
+    NSS_NoDB_Init(".");
+
 /*
  *      read all entries from all directories hashing name and value, and make
  *      a bitmaps of who has each entry.  Flag those entries where at least