MXS-2621: Add test case

The test reproduces the problem with lower_case_table_names.

maxscale-system-test/mxs2621_lower_case_tables.cpp

@@ -0,0 +1,15 @@
+/**
+ * MXS-2621: Incorrect SQL if lower_case_table_names is used.
+ * https://jira.mariadb.org/browse/MXS-2621
+ */
+
+#include "testconnections.h"
+
+int main(int argc, char* argv[])
+{
+    TestConnections test(argc, argv);
+    test.maxscales->connect();
+    test.try_query(test.maxscales->conn_rwsplit[0], "SELECT 123");
+    test.maxscales->disconnect();
+    return test.global_result;
+}