Rollup merge of #150953 - uefi-fs-copy, r=joboet

std: sys: fs: uefi: Implement copy

- Using the implementation from sys::fs::common since ther is no built-in copy implementation in UEFI.
- Tested with OVMF on QEMU.

@rustbot label +O-UEFI

library/std/src/sys/fs/uefi.rs

@@ -6,7 +6,7 @@ use crate::fs::TryLockError;
 use crate::hash::Hash;
 use crate::io::{self, BorrowedCursor, IoSlice, IoSliceMut, SeekFrom};
 use crate::path::{Path, PathBuf};
-pub use crate::sys::fs::common::{Dir, remove_dir_all};
+pub use crate::sys::fs::common::{Dir, copy, remove_dir_all};
 use crate::sys::pal::{helpers, unsupported};
 use crate::sys::time::SystemTime;
 
@@ -541,10 +541,6 @@ pub fn canonicalize(p: &Path) -> io::Result<PathBuf> {
     crate::path::absolute(p)
 }
 
-pub fn copy(_from: &Path, _to: &Path) -> io::Result<u64> {
-    unsupported()
-}
-
 fn set_perm_inner(f: &uefi_fs::File, perm: FilePermissions) -> io::Result<()> {
     let mut file_info = f.file_info()?;