[clang] [Clang][Driver][Test] Created test for unsupported driver options (PR #120900)

[via cfe-commits]

GeorgeKA wrote:

@Maetveis 

All of the Visibility fields appear to be not null, but that's a good check to add anyway. Thanks. After adding it though, the same failures occur. Here's an example. Maybe there's a gap in my understanding:

The script generates tests for both flang & clang -cc1as when looking at the O_flag option. cc1as outputs the unexpected error message, but flang does not.
```
$ clang -cc1as -O_flag -help 2>&1 | less
clang -cc1as: error: unknown argument: '-O_flag'

$ flang -O_flag -help 2>&1 | less
<regular help message>
```
These are the steps I'm taking for manual validation:
1) Generate JSON dump for Options.td
`llvm-tblgen -I <llvm repo>/llvm/include <llvm repo>/clang/include/clang/Driver/Options.td -dump-json | jq . > Options.td.json`
2) Navigate to `"O_flag": {`
3) "`Group`" is null, so no extra visibilities to check
4) "`Visibility`" includes DefaultVis, CC1Option, & FC1Option, which leaves unsupported Visibilities as CC1AsOption, CLOption, DXCOption, FlangOption, so the script generates run lines & checks for these four.

Drivers/visibilities include:
	"CC1AsOption"
	"CC1Option"
	"CLOption"
	"DXCOption"
	"DefaultVis"
	"FC1Option"
	"FlangOption"


https://github.com/llvm/llvm-project/pull/120900