Revert "cryptonote_protocol: drop peers we can't download from when syncing"

This reverts commit a96c1a46d4.

src/cryptonote_protocol/cryptonote_protocol_handler.inl

@@ -342,11 +342,6 @@ namespace cryptonote
 
     if(m_core.have_block(hshd.top_id))
     {
-      if (target > hshd.current_height)
-      {
-        MINFO(context << "peer is not ahead of us and we're syncing, disconnecting");
-        return false;
-      }
       context.m_state = cryptonote_connection_context::state_normal;
       if(is_inital && target == m_core.get_current_blockchain_height())
         on_connection_synchronized();