crimson/osd: fix wrong log arguments in get_option_value and _get_early_config

crimson/osd: fix wrong log arguments in get_option_value and _get_early_config

Both log calls referenced option.config_key (the ceph config key name)
where option.option_name (the CLI flag) was intended:

  logger().warn("get_option_value --option_name {} ...", option.config_key);
  logger().info("Configure option_name {} with value : {}", option.config_key, ...);

Fix both to log option.option_name. Also remove the trailing space
before the colon in the info format string.

Signed-off-by: Kefu Chai <k.chai@proxmox.com>