This marks all `<PACKAGENAME>_FOUND` result variables as deprecated
where possible (for `<PackageName>` find modules) to make it clearer
which variable to use.
In CMake 3.3, the FindPackageHandleStandardArgs module was refactored to
set both `<PackageName>_FOUND` and uppercase `<PACKAGENAME>_FOUND`
result variables to the same values. Before that, the FOUND_VAR argument
could be used to set the result variable.
* FindMatlab: Uppercased MATLAB_FOUND is not mentioned as it was never
documented.
* Documentation for FindPythonInterp and FindPythonLibs modules synced
accordingly to their deprecation (3.12 instead of 4.2).
* OPENGL_FOUND: deprecation version synced with other find modules.
* DevIL_FOUND was introduced in CMake 3.8. The uppercased variant not
mentioned as it was previously never documented.
Fixes: #27242
- Added intro code blocks showing how to use find modules.
- Synced modules documentation.
- Extended few examples to make the intro code blocks fit into the
modules descriptions.
- Synced some RST formatting, variables descriptions and positions.
- Removed few redundant internal comments.
Issue: #26555
- Synced module documentation with other similar find modules.
- Added examples section describing module usage, highlighting the
imported target, and how to override ODBC configuration through
cache variables on Unix-like systems. Some exotic or custom ODBC
implementations might sometimes need such steps.