lib/xz: Add fall-through comments to a switch statement

It's good style. I was also told that GCC 7 is more strict and might
give a warning when such comments are missing.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Suggested-by: Andrei Borzenkov <arvidjaar@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
1 file changed