Bug 259562

It looks like 219104@main "build-jsc should invoke make instead of calling xcodebuild directly" broke the --analyze and --coverage options of build-jsc for Apple ports (and nowadays also build-webgpu since this code was moved from build-jsc to BuildSubproject.pm). (These options never worked for CMake ports.) When the flags are used, then additional XCode build options get added to @additionalSupportOptions, but this variable is no longer used anywhere. I don't know how to fix it.

Maybe the flags are not too valuable, since it took three years for us to notice, and I only noticed while trying to fix an unrelated bug (bug #259527). We should consider removing the flags. If we fix the flags instead of removing them, consider adjusting the help output to indicate they only work with XCode and not CMake.