make check failed for out of tree builds because we didn't set up
WESTON_TEST_REFERENCE_PATH in weston-tests-env
Signed-off-by: Derek Foreman <derekf@osg.samsung.com>
Reviewed-by: Bryce Harrington <bryce@osg.samsung.com>
Tested-by: Bryce Harrington <bryce@osg.samsung.com>