Remove `in_band_lifetimes` from `rustc_codegen_ssa`
See #91867 for more information.
In `compiler/rustc_codegen_ssa/src/coverageinfo/map.rs`, there are several functions with an explicit `'a` lifetime but only a single `&'a self` parameter. These lifetimes should be redundant given lifetime elision, unless the existential `impl Iterator` has weird issues regarding that. Should the redundant lifetimes be removed?