Auto merge of #43616 - mbrubeck:fnv, r=michaelwoerister

Remove unused FnvHash code

None

Author: bors

src/librustc_data_structures/fnv.rs

@@ -65,7 +65,6 @@ pub mod snapshot_vec;
 pub mod stable_hasher;
 pub mod transitive_relation;
 pub mod unify;
-pub mod fnv;
 pub mod fx;
 pub mod tuple_slice;
 pub mod veccell;