bisect--helper: report actual bisect_state() argument on error
The strvec "args" in bisect_run() is initialized and cleared, but never
added to. Nevertheless its first member is printed when reporting a
bisect_state() error. That's not useful, since it's always NULL.
Before
d1bbbe45df (bisect--helper: reimplement `bisect_run` shell
function in C, 2021-09-13) the intended new state was reported if it
could not be set. Reinstate that behavior and remove the unused strvec.
Reported-by: Ramkumar Ramachandra <r@artagnon.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>