lib/xz: Put CRC32_POLY_LE in xz_private.h

[Michael Ellerman]

On Fri, 2018-09-21 at 02:54:31 UTC, Joel Stanley wrote:
> This fixes a regression introduced by faa16bc404d72a5 ("lib: Use
> existing define with polynomial").
> 
> The cleanup added a dependency on include/linux, which broke the PowerPC
> boot wrapper/decompresser when KERNEL_XZ is enabled:
> 
>   BOOTCC  arch/powerpc/boot/decompress.o
>  In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:233,
>                  from arch/powerpc/boot/decompress.c:42:
>  arch/powerpc/boot/../../../lib/xz/xz_crc32.c:18:10: fatal error:
>  linux/crc32poly.h: No such file or directory
>   #include <linux/crc32poly.h>
>            ^~~~~~~~~~~~~~~~~~~
> 
> The powerpc decompresser is a hairy corner of the kernel. Even while building
> a 64-bit kernel it needs to build a 32-bit binary and therefore avoid including
> files from include/linux.
> 
> This allows users of the xz library to avoid including headers from
> 'include/linux/' while still achieving the cleanup of the magic number.
> 
> Fixes: faa16bc404d72a5 ("lib: Use existing define with polynomial")
> Reported-by: Meelis Roos <mroos at linux.ee>
> Reported-by: kbuild test robot <lkp at intel.com>
> Suggested-by: Christophe LEROY <christophe.leroy at c-s.fr>
> Signed-off-by: Joel Stanley <joel at jms.id.au>
> Tested-by: Meelis Roos <mroos at linux.ee>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/242cdad873a75652f97c35aad61270

cheers