get_patch_filename(): simplify function signature Most functions that emit to a strbuf take the strbuf as their first parameter; make this function follow suit. The serial number of the patch being emitted (nr) and suffix used for patch filename (suffix) are both recorded in rev_info; drop these separate parameters and pass the rev_info directly. Signed-off-by: Junio C Hamano <gitster@pobox.com>