"-p" checking for oclint/clang-tidy always fails

[rambo]

if "-p" is specified alone (so the "-p" in args -check could succeed) clang-tidy complains about missing value.

If it's specified correctly for clang-tidy ("-p=cmake-build-debug") then the check fails and the -D is added which makes clang-tidy not find for example included libraries...

I will submit a PR soonish.

[pocc]

Thanks for noticing this. I think I'm just going to delete the add_if_missing for -- -DCMAKE_EXPORT_COMPILE_COMMANDS=ON because the stderr due to its lack is useful information. I saw your commit, which also fixes this issue.