INSP: Add E0510 check

[kuksag]

changelog:

[kuksag]

There's a false negative for situation like rust-lang/rust#27282 (mutation through lambda):

{
    let mut x = &mut &Some(&2);
    match **x {
        None => panic!("unreachable"),
        Some(&_) if {
            (|| { *x = &None; })();
            //~^ ERROR cannot mutably borrow `x` in match guard [E0510]
            false
        } => {}
        Some(&a) if { // this binds to garbage if we've corrupted discriminant
            println!("{}", a);
            panic!()
        } => {}
        _ => panic!("unreachable"),
    }
}