(reland) [clang] Warn [[clang::lifetimebound]] misusages on types (#118501)

This relands #118281 as-is, after it got reverted in commit
356df2dd72e8299b5de58e9390283110c19f7c76. The reland can go in after we
fixed some downstream codebases that had incorrectly placed attributes.

Original commit description:

> Emit the "cannot be applied to types" warning instead of silently
ignoring the attribute when it's attempted to be used on a type (instead
of a function argument or the function definition).
>
> Before this commit, the warning has been printed when the attribute
was (mis)used on a decl-specifier, but not in other places in a
declarator.
>
> Examples where the warning starts being emitted with this commit:
>
> ```
>   int * [[clang::lifetimebound]] x;
>
>   void f(int * [[clang::lifetimebound]] x);
>
>   void g(int * [[clang::lifetimebound]]);
> ```
>
> Note that the last example is the case of an unnamed function
parameter. While in theory Clang could've supported the
`[[clang::lifetimebound]]` analysis for unnamed parameters, it doesn't
currently, so the commit at least makes the situation better by
highlighting this as a warning instead of a silent ignore - which was
reported at #96034.

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