http: drop unused parameter from start_object_request()
We take a "walker" parameter for the request, but don't actually look at
it. This is due to
5424bc557f (http*: add helper methods for fetching
objects (loose), 2009-06-06). Before then, we consulted the "walker"
struct to tell us if we should be verbose, but now those messages are
printed elsewhere.
Let's drop the unused parameter to make -Wunused-parameter happy.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>