[clang] [Clang] Add wraps attribute (for granular integer overflow handling) (PR #86618)

[Justin Stitt via cfe-commits]

JustinStitt wrote:

In an effort to appease the build bot, I am adding a `-W` flag to turn of `warn_wraps_attr_var_decl_type_not_integer` which yells at users for trying to add `__attribute__((wraps))` to things that don't really wrap in the traditional sense.

https://github.com/llvm/llvm-project/pull/86618