hiffy use of mutable statics is possibly unsound

[cbiffle]

With the latest toolchain update we're getting these warnings from hiffy.

warning: creating a shared reference to mutable static is discouraged
   --> task/hiffy/src/main.rs:173:29
    |
173 |         let data = unsafe { &HIFFY_DATA };
    |                             ^^^^^^^^^^^ shared reference to mutable static
    |
    = note: for more information, see issue #114447 <https://github.com/rust-lang/rust/issues/114447>
    = note: this will be a hard error in the 2024 edition
    = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
help: use `addr_of!` instead to create a raw pointer
    |
173 |         let data = unsafe { addr_of!(HIFFY_DATA) };
    |                             ~~~~~~~~~~~~~~~~~~~~

I can't convince myself by local inspection that what the task is doing with statics is sound. Someone more familiar with the code will need to go in there and fix it.