Unabled to use SIFT feature with opencv 4.5.4

[cleprt]

I am using visp on Ubuntu 22 with opencv 4.5.4 (installed via apt libopencv-dev).

The use of vpKeyPoint::initDetector(const std::string &detectorName) with "SIFT" fails in the new master branch while it worked for me on the commit 70ddb40 with the same opencv version.

I feel like the line https://github.com/lagadic/visp/blob/master/modules/vision/src/key-point/vpKeyPoint.cpp#L1784 does not take all cases in consideration as with opencv 4.5.4 I do have the file opencv2/features2d/features2d.hpp (which means def of HAVE_OPENCV_FEATURES) and not xfeatures2d.hpp.

[fspindle]

This issue is to make in relation to PR #1522 that introduced compat with OpenCV 5.x.

[fspindle]

@cleprt Should be fixed in PR #1555