btrfs: add test regarding clearing compression flag/property
Regression test for btrfs where removing the flag FS_COMPR_FL
(chattr -c) from an inode wouldn't clear its compression property.
This was fixed in the following linux kernel patch:
Btrfs: add missing compression property remove in btrfs_ioctl_setflags
Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Disseldorp <ddiss@suse.de> Signed-off-by: Dave Chinner <david@fromorbit.com>