xfs/076: fix broken mkfs filtering

xfs/076: fix broken mkfs filtering

The test does not do what it says on the packet - the mkfs output is
not actually passed to the mkfs filter, so it doesn't know what
inode size mkfs actually used. Hence CHUNK_SIZE ends up being
calculated as 0, and that means it enters an endless loop because
offset never decreases.

Fix it by adding the missing line continuation.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Zorro lang <zlang@redhat.com>
Signed-off-by: Zorro Lang <zlang@kernel.org>