Fix borks from the latest nightly

The `cargo doc` build started to fail with the rolling of `doc_auto_cfg` into
`doc_cfg`, so now we don't build docs for deps (as we can't reasonably update
`generic-array` at this time).

`home` has been patched as we are able to, not as a direct requirement of this
PR.

patches/home/src/lib.rs

@@ -0,0 +1 @@
+pub use std::env::home_dir;