MXS-1275: SetSqlModeParser moved under MySQLClient

That's where it belongs as it is only the mysql client protocol that
will use it. It's a bit unfortunate that the qc test program compare
now needs to include a file from a protocol module directory, but
the fact is that the query classifier implementation and the test
programs should actually be *under* the mysql client protocol module.

server/modules/protocol/MySQL/MySQLClient/test/CMakeLists.txt

@@ -0,0 +1,4 @@
+add_executable(test_setsqlmodeparser test_setsqlmodeparser.cc)
+target_link_libraries(test_setsqlmodeparser maxscale-common)
+
+add_test(test_setsqlmodeparser test_setsqlmodeparser)