Inconsistent handling of --repo command line option

[tpapaioa]

When calling an ostree command with the --repo option before the subcommand, the option must be in the format --repo=REPO, and not --repo REPO:

# ostree --repo ./ostree refs
Usage:
  ostree [OPTION…] COMMAND
[...]
error: Unknown option --repo

# ostree --repo=./ostree refs
my_branch

When the --repo option follows the subcommand, however, either format will work:

# ostree refs --repo=./ostree
my_branch

# ostree refs --repo ./ostree
my_branch

It should be possible to use either format when the --repo option precedes the ostree subcommand.