Saturating integer division. Computes `self / rhs`,
saturating at the numeric bounds instead of overflowing.
# Panics
This function will panic if `rhs` is zero.
# Examples
Basic usage:
```
# use ::exint::primitive::*;
# ::exint::uint! {
assert_eq!(5_u24.saturating_div(2_u24), 2_u24);
# }
```