Work out how to lint against `u64::pow`

[michaelsproul]

Description

As discussed here #2350 (comment), the disallowed-methods Clippy lint doesn't seem to work for associated functions on primitive types. This lint was originally created by a Lighthouse contributor for #1621, and has been improved by other Clippy contributors since!

To resolve this issue we should put some print statements in Clippy to work out what AST it sees for functions like u64::pow, and then work out how to incorporate detection of those AST nodes.

Version

Rust 1.52.1 (stable)

[Ifechukwudaniel]

Hey I would love to do this

[michaelsproul]

@Ifechukwudaniel thanks that would be great!