Bounds check is not eliminated `i != count` vs `i < count`

```cpp
#define _GLIBCXX_ASSERTIONS
#include <vector>

void foo(std::vector<double> &vec)
{
   auto count = size(vec);
   for (decltype(count) i = 0; i != count; ++i)
     vec[i] += 1;
}
```
`-mllvm -enable-constraint-elimination` does not help.
With `i < count` bounds check is eliminated.
https://godbolt.org/z/s6Gbsqvor