Tests no longer run in a out of source build due to missing replace utiltiy

When i run the tests from inside the cmake BUILD_DIR (out of source), mtr can no longer find the replace utility.

mysql-test-run: *** ERROR: Could not find any of /var/tmp/portage/dev-db/mariadb-5.5.41/work/mysql/extra/replace /var/tmp/portage/dev-db/mariadb-5.5.41/work/mariadb-5.5.41_build/client/replace

replace is built into ${BUILD_DIR}/extra, while mtr is searching in ${BUILD_DIR}/client (or ${S}/extra for in-source builds.. not default)

This seems to be a result of the merge upstream:
https://bazaar.launchpad.net/~maria-captains/maria/5.5/revision/4393/mysql-test/mysql-test-run.pl#mysql-test/mysql-test-run.pl

# ----------------------------------------------------

# replace

# ----------------------------------------------------

my $exe_replace= mtr_exe_exists(vs_config_dirs('extra', 'replace'),

                                 "$basedir/extra/replace",

                                 "$path_client_bindir/replace");

  $ENV{'REPLACE'}= native_path($exe_replace);