xfs/191: remove broken test

xfs/191: remove broken test

Test has been marked broken for a long time. Original intent of
validating all mkfs.xfs input is not realistic, nobody is going to
try to make that happen.

Remove it as it serves no useful purpose except to have a whacky
unique name that nobody expects or codes for.

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