get_maintainer: add --substatus for reporting subsystem status - fix

get_maintainer: add --substatus for reporting subsystem status - fix

The automatically enabled --substatus can break existing scripts that do
not disable --rolestats.  Require that script output goes to a terminal to
enable it automatically.

Link: https://lkml.kernel.org/r/66c2bf7a-9119-4850-b6b8-ac8f426966e1@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>