config: Collect updatable localdb files to 'localdb_files' key

ols/config.py

@@ -190,6 +190,17 @@ def get_config():
                   if b.get('type', '') in ('m8b',)):
         fix_datapath(wconf, 'datafile')
 
+    # Store updatable localdb files
+    localdb_files = []
+    for wconf in (b for b in conf.get('resolver', {}).values()
+                  if b.get('type', '') in ('localdb',)):
+        if wconf.get('update', False):
+            dbfile = wconf.get('db')
+            if dbfile is not None:
+                localdb_files.append(dbfile)
+
+    conf['localdb_files'] = localdb_files
+
     return conf