MXS-1765: Update current command for KILL processing

The current command needs to be updated before the queries are actually
routed. This allows the KILL command detection and processing to correctly
work.

server/modules/protocol/MySQL/mariadbclient/mysql_client.cc

@@ -972,6 +972,10 @@ gw_read_normal_data(DCB *dcb, GWBUF *read_buffer, int nbytes_read)
             return 0;
         }
 
+        // Update the current command, required by KILL command processing
+        MySQLProtocol *proto = (MySQLProtocol*)dcb->protocol;
+        proto->current_command = (mxs_mysql_cmd_t)mxs_mysql_get_command(read_buffer);
+
         set_qc_mode(session, &read_buffer);
 
         session_retain_statement(session, read_buffer);