FindOpenCL: Add detection of OpenCL 2.1 and 2.2
The current FindOpenCL is missing a check for 2.1 and 2.2, causing it to never report a version higher than 2.0.
Topic-rename: FindOpenCL-more-versions
Edited by Brad King
The current FindOpenCL is missing a check for 2.1 and 2.2, causing it to never report a version higher than 2.0.
Topic-rename: FindOpenCL-more-versions