Revert "Remove unnecessary windows.h include"

Revert "Remove unnecessary windows.h include"

This reverts commit e6d1e13b2880ab0e6166e5ed168df7e6e0de943b.

We do need this (for the CLI tools).

Fixes a build failure on MinGW:
  CC       tar/bsdtar-bsdtar.o
In file included from tar/bsdtar_platform.h:62:0,
                 from tar/bsdtar.c:26:
./libarchive/archive_entry.h:250:64: error: unknown type name 'BY_HANDLE_FILE_INFORMATION'
 __LA_DECL void archive_entry_copy_bhfi(struct archive_entry *, BY_HANDLE_FILE_INFORMATION *);
                                                                ^