[U-Boot] [U-Boot, v10, 09/10] efi: Correct the operation of efi_file_write()

[Alexander Graf]

> We should not directly cast between pointers and addresses since it breaks
> sandbox. Fix this and simplify the code in file_read().
> 
> Signed-off-by: Simon Glass <sjg at chromium.org>

Thanks, applied to efi-next

Alex