builtin/multi-pack-index.c: don't handle 'progress' separately
Now that there is a shared 'flags' member in the options structure,
there is no need to keep track of whether to force progress or not,
since ultimately the decision of whether or not to show a progress meter
is controlled by a bit in the flags member.
Manipulate that bit directly, and drop the now-unnecessary 'progress'
field while we're at it.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>