MXS-2264: Fix table versioning

The table versions are now stored in memory and are only resolved on
startup. This simplifies things and removes the need to know where the
data is stored as that information is not available to the Rpl class.

server/modules/routing/avrorouter/rpl.hh

@@ -285,6 +285,8 @@ private:
     pcre2_match_data* m_md_match;
     pcre2_match_data* m_md_exclude;
 
+    std::unordered_map<std::string, int> m_versions;    // Table version numbers per identifier
+
     void              handle_query_event(REP_HEADER* hdr, uint8_t* ptr);
     bool              handle_table_map_event(REP_HEADER* hdr, uint8_t* ptr);
     bool              handle_row_event(REP_HEADER* hdr, uint8_t* ptr);