Rollup merge of #70133 - hermitcore:libpanic_unwind, r=nikomatsakis

remove unused imports

patch is required to avoid compiler errors by building src/libpanic_unwind/hermit.rs

Author: JohnTitor

Diff for: src/libpanic_unwind/hermit.rs

@@ -4,7 +4,6 @@
 
 use alloc::boxed::Box;
 use core::any::Any;
-use core::ptr;
 
 pub unsafe fn cleanup(_ptr: *mut u8) -> Box<dyn Any + Send> {
     extern "C" {