xfs: refactor xfs/299 for crc feature pre-checkup

xfs: refactor xfs/299 for crc feature pre-checkup

Refactor xfs/299 to make use of those two crc related pre-checkup
routines, and remove the super block number from the golden output
file as it does not make sense IMO.  Also, filter out *EXPERIMENTAL*
string from mkfs.xfs output as those contents would be removed once
crc feature becomes stable.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>