lib/base: heim_config_parse_dir_multi do not overwrite error

In heim_config_parse_dir_multi() do not call heim_enomem(context)
when returning ENOMEM when a better error has already been set in
the context.  Just return ENOMEM.

Change-Id: I9bd9de552b2b04b5a7328ac635e911d6e95422ef

lib/base/config_file.c

@@ -527,7 +527,7 @@ heim_config_parse_dir_multi(heim_context context,
         free(path);
         if (ret == ENOMEM) {
             (void) closedir(d);
-            return heim_enomem(context);
+            return ENOMEM;
         }
         /* Ignore malformed config files so we don't lock out admins, etc... */
     }