btrfs/205: skip test when running with nodatasum mount option

btrfs/205: skip test when running with nodatasum mount option

Currently the test fails when we pass "-o nodatasum" in MOUNT_OPTIONS and
the reason is because we enable compression, with "chattr +c", on a file
and then try to clone from it to a file with nodatasum inherited from the
mount options, which results in the clone ioctl to fail with -EINVAL since
it's not possible to clone from datasum to nodatasum and vice-versa.

So skip the test if nodatasum is a mount option.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Zorro Lang <zlang@kernel.org>