builtin/multi-pack-index.c: inline 'flags' with options
Subcommands of the 'git multi-pack-index' command (e.g., 'write',
'verify', etc.) will want to optionally change a set of shared flags
that are eventually passed to the MIDX libraries.
Right now, options and flags are handled separately. That's fine, since
the options structure is never passed around. But a future patch will
make it so that common options shared by all sub-commands are defined in
a common location. That means that "flags" would have to become a global
variable.
Group it with the options structure so that we reduce the number of
global variables we have overall.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>