docs: panic: Disclaimer about console verbosity when using panic_print with pstore

Users of panic_print / panic_sys_info are usually aware of the potentially
huge amount of information displayed with such options - their goal by
using them is indeed to dump more information during panic!

What might come unnoticed at first is the impact that the console_verbose()
call on panic path has, specially in cases that users rely on pstore as
a means to collect the panic logs. Recent experience shows that dumping
all tasks in an ARM64 system (with qcom_geni tty driver) gets a 2 minute
delay on panic time due to writing such information to console. But in
that case, pstore was used, so there was no need for console printing,
and suppressing that reduced the full time to less than 0.5 second.

The option "printk.console_no_auto_verbose" aims exactly at this use
case: avoid automatically increasing the loglevel during panic path.
So, let's officially document this to avoid users wasting their time
either on long panic printing or debugging the panic delays.

While at it, improve the readability of the panic_print text, by
adding some line breaks.

Suggested-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Bradley Morgan <include@grrlz.net>
Reviewed-by: Feng Tang <feng.tang@linux.alibaba.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260819183419.2203903-1-gpiccoli@igalia.com>

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