tools: ynl: cli: extract the event/notify handling in --list-attrs

tools: ynl: cli: extract the event/notify handling in --list-attrs

Event and notify handling is quite different from do / dump
handling. Forcing it into print_mode_attrs() doesn't really
buy us anything as events and notifications do not have requests.
Call print_attr_list() directly. Apart form subjective code
clarity this also removes the word "reply" from the output:

Before:

  Event reply attributes:

Now:

  Event attributes:

Tested-by: Gal Pressman <gal@nvidia.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20260110233142.3921386-7-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>