System information (version)

• OpenCV => 3.3.1
• Operating System / Platform => Ubuntu 16.04
• Compiler => /usr/bin/c++ (ver 5.4.0)

Detailed description

FlannBasedMatcher has two methods, constructor FlannBasedMatcher and create() that can't be wrapped without optional flann module but CV_WRAP ignores #ifdef HAVE_OPENCV_FLANN.

Steps to reproduce

cmake -DBUILD_LIST=features2d,python2 .. && make -j8