check: treat _check_{test,scratch}_fs failures as test failures

check: treat _check_{test,scratch}_fs failures as test failures

Currently if _check_test_fs and/or _check_scratch_fs find corruption,
the test itself is still reported as pass, like

	[root@hp-dl388eg8-01 xfstests]# ./check xfs/071 xfs/072
	FSTYP         -- xfs (non-debug)
	PLATFORM      -- Linux/x86_64 hp-dl388eg8-01 3.18.0-rc7+
	MKFS_OPTIONS  -- -f -bsize=4096 /dev/sda6
	MOUNT_OPTIONS -- -o context=system_u:object_r:nfs_t:s0 /dev/sda6 /mnt/testarea/scratch

	xfs/071  2s
	_check_xfs_filesystem: filesystem on /dev/sda6 is inconsistent (r) (see /root/xfstests/results//xfs/071.full)
	xfs/072  1s
	Ran: xfs/071 xfs/072
	Passed all 2 tests

	[root@hp-dl388eg8-01 xfstests]# echo $?
	0

Usually it's not a problem, but it does confuse scripts that depend on
return value of check. Update check to treat _check_{test,scratch}_fs
failures as test failures too, new test output is like

	[root@hp-dl388eg8-01 xfstests]# ./check xfs/071 xfs/072
	FSTYP         -- xfs (non-debug)
	PLATFORM      -- Linux/x86_64 hp-dl388eg8-01 3.18.0-rc7+
	MKFS_OPTIONS  -- -f -bsize=4096 /dev/sda6
	MOUNT_OPTIONS -- -o context=system_u:object_r:nfs_t:s0 /dev/sda6 /mnt/testarea/scratch

	xfs/071 2s ... 2s
	_check_xfs_filesystem: filesystem on /dev/sda6 is inconsistent (r) (see /root/xfstests/results//xfs/071.full)
	xfs/072 1s ... 1s
	Ran: xfs/071 xfs/072
	Failures: xfs/071
	Failed 1 of 2 tests

	[root@hp-dl388eg8-01 xfstests]# echo $?
	1

Signed-off-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>