[UBSan] Implement src:*=sanitize for UBSan (#140529)

Background: https://github.com/llvm/llvm-project/issues/139128

It is a draft implementation for "src:*=sanitize". It should be applied
to all sanitizers.

Any srcs assigned to the sanitize category will have their sanitizer
instrumentation remained ignored by "src:". For example,

```
src:*
src:*/test1.cc=sanitize
```

`test1.cc` will still have the UBSan instrumented.

Conflicting entries are resolved by the latest entry, which takes
precedence.

```
src:*
src:*/mylib/*=sanitize
src:*/mylib/test.cc
```
`test.cc` does not have the UBSan check (In this case,
`src:*/mylib/test.cc` overrides `src:*/mylib/*=sanitize` for `test.cc`).

```
src:*
src:*/mylib/test.cc
src:*/mylib/*=sanitize
```

`test1.cc` has the UBSan instrumented (In this case,
`src:*/mylib/*=sanitize` overrides `src:*/mylib/test.cc`).

Documents update will be in a new PR.

0 files changed, 0 insertions, 0 deletions