libarchive: fix ext2fs build race error condition

libarchive: fix ext2fs build race error condition

libarchive looks for ext2fs headers during configure, and if it finds
them it will expect to find them during compile, or on the rare occasion
when they aren't it will fail:

 libarchive/archive_entry.c:59:55: fatal error: ext2fs/ext2_fs.h: No such file or directory

As we just need headers for some type constants, let's re-use headers
from tools/e2fsprogs package which are always available.

Reported-by: Adam Dov <adov@maxlinear.com>
Suggested-by: Paul Eggleton <paul.eggleton@linux.intel.com>
References: https://git.yoctoproject.org/poky/commit/?id=f0b9a7cf9f80be1917e45266fa201f464a28c1e5
Signed-off-by: Petr Štetiar <ynezz@true.cz>