Commit 7d6cb10b ("grep: Add the option '--line-number'", 2011-03-28)
introduced the --line-number option and added its description to OPTIONS
section, but forgot to update SYNOPSIS.
Signed-off-by: Michał Kiedrowicz <michal.kiedrowicz@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>