lib/lzo: Update LZO compression to current upstream version

commit 8b975bd3f9089f8ee5d7bbfd798537b992bbc7e7 upstream.

This commit updates the kernel LZO code to the current upsteam version
which features a significant speed improvement - benchmarking the Calgary
and Silesia test corpora typically shows a doubled performance in
both compression and decompression on modern i386/x86_64/powerpc machines.

Signed-off-by: Markus F.X.J. Oberhumer <markus@oberhumer.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>