btrfs/173: Adjust compress file check

Following kernel commit "btrfs: add missing check for nocow and
compression inode flags" the enforcement of "can't set +c on a +C" file
has been moved to the ioctl code. Modify the test to account for this.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

tests/btrfs/173

@@ -48,9 +48,7 @@ swapoff "$SCRATCH_MNT/swap" >/dev/null 2>&1
 echo "Compressed file"
 rm -f "$SCRATCH_MNT/swap"
 _format_swapfile "$SCRATCH_MNT/swap" $(($(get_page_size) * 10))
-$CHATTR_PROG +c "$SCRATCH_MNT/swap"
-swapon "$SCRATCH_MNT/swap" 2>&1 | _filter_scratch
-swapoff "$SCRATCH_MNT/swap" >/dev/null 2>&1
+$CHATTR_PROG +c "$SCRATCH_MNT/swap" 2>&1 | grep -o "Invalid argument while setting flags"
 
 status=0
 exit

tests/btrfs/173.out

@@ -2,4 +2,4 @@ QA output created by 173
 COW file
 swapon: SCRATCH_MNT/swap: swapon failed: Invalid argument
 Compressed file
-swapon: SCRATCH_MNT/swap: swapon failed: Invalid argument
+Invalid argument while setting flags