file-hashing: restore 'force-md5'

We don't want to break existing setups.

Do issue a warning that a new option is available.

src/util-file.c

@@ -134,6 +134,22 @@ void FileForceHashParseCfg(ConfNode *conf)
 
     ConfNode *forcehash_node = NULL;
 
+    /* legacy option */
+    const char *force_md5 = ConfNodeLookupChildValue(conf, "force-md5");
+    if (force_md5 != NULL) {
+        SCLogWarning(SC_ERR_DEPRECATED_CONF, "deprecated 'force-md5' option "
+                "found. Please use 'force-hash: [md5]' instead");
+
+        if (ConfValIsTrue(force_md5)) {
+#ifdef HAVE_NSS
+            FileForceMd5Enable();
+            SCLogInfo("forcing md5 calculation for logged files");
+#else
+            SCLogInfo("md5 calculation requires linking against libnss");
+#endif
+        }
+    }
+
     if (conf != NULL)
         forcehash_node = ConfNodeLookupChild(conf, "force-hash");