Change RemoteMirror#sync? to be semantically sound

app/models/remote_mirror.rb

@@ -89,11 +89,11 @@ class RemoteMirror < ActiveRecord::Base
   end
 
   def sync?
-    !enabled?
+    enabled?
   end
 
   def sync
-    return if sync?
+    return unless sync?
 
     if recently_scheduled?
       RepositoryUpdateRemoteMirrorWorker.perform_in(backoff_delay, self.id, Time.now)

ee/app/models/ee/remote_mirror.rb

@@ -3,7 +3,7 @@ module EE
     extend ActiveSupport::Concern
 
     def sync?
-      super || ::Gitlab::Geo.secondary?
+      super && !::Gitlab::Geo.secondary?
     end
   end
 end