bes the memory ordering of this operation.
Possible values are [`SeqCst`], [`Release`] and [`Relaxed`].

# Panics

Panics if `order` is [`Acquire`] or [`AcqRel`].

# Examples

```
use portable_atomic::{AtomicIsize, Ordering};

let some_var = AtomicIsize::new(5);

some_var.store(10, Ordering::Relaxed);
assert_eq!(some_var.load(Ordering::Relaxed), 10);
```