fstests: fix group check in new script
In the tests/*/group files, group names are found in the Nth columns of
the file, where N > 1. The grep expression to warn about unknown groups
is not correct (since it currently checks column 1), so fix this.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>