Prefer a consistent naming for the --merge argument.
Fixes: 3b51ab4bf
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200529144527.1943527-1-eblake@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>