Remove iter::zip feature gate from clippy

Author: Patrick-Poitras

src/tools/clippy/clippy_lints/src/lib.rs

@@ -3,7 +3,6 @@
 #![feature(box_patterns)]
 #![feature(drain_filter)]
 #![feature(in_band_lifetimes)]
-#![feature(iter_zip)]
 #![feature(once_cell)]
 #![feature(rustc_private)]
 #![feature(stmt_expr_attributes)]

src/tools/clippy/clippy_utils/src/lib.rs

@@ -1,6 +1,5 @@
 #![feature(box_patterns)]
 #![feature(in_band_lifetimes)]
-#![feature(iter_zip)]
 #![feature(let_else)]
 #![feature(rustc_private)]
 #![feature(control_flow_enum)]