[clang] Diagnose misuse of the cleanup attribute (PR #80040)

[Bhuminjay Soni via cfe-commits]

11happy wrote:

```
extern void free(void *);
extern void *malloc(size_t size);
void t8(void) {
  void *p __attribute__((cleanup(free))) = malloc(10); // expected-warning{{attempt to call free on non-heap object 'p'}}
}
```
 I added  this, but 
I am getting this error: (Sorry if its a silly doubt)

```
error: 'expected-warning' diagnostics expected but not seen: 
  File /home/happy/LLVM/llvm-project/clang/test/Sema/attr-cleanup.c Line 55: attempt to call free on non-heap object 'p'
error: 'expected-warning' diagnostics seen but not expected: 
  (frontend): attempt to call free on non-heap object 'p'
2 errors generated.
```

https://github.com/llvm/llvm-project/pull/80040