When 20d1c652 (parse-options: remove unused OPT_SET_PTR, 2014-03-30)
removed OPT_SET_PTR, the comment in the header that describes what
the option did to defval field was left behind by mistake. Remove
it.
Signed-off-by: Ivan Ukhov <ivan.ukhov@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>