netlink: specs: support ipv4-or-v6 for dual-stack fields

netlink: specs: support ipv4-or-v6 for dual-stack fields

Since commit 1b255e1beabf ("tools: ynl: add ipv4-or-v6 display hint"), we
can display either IPv4 or IPv6 addresses for a single field based on the
address family. However, most dual-stack fields still use the ipv4 display
hint. This update changes them to use the new ipv4-or-v6 display hint and
converts IPv4-only fields to use the u32 type.

Field changes:
  - v4-or-v6
    - IFA_ADDRESS, IFA_LOCAL
    - IFLA_GRE_LOCAL, IFLA_GRE_REMOTE
    - IFLA_VTI_LOCAL, IFLA_VTI_REMOTE
    - IFLA_IPTUN_LOCAL, IFLA_IPTUN_REMOTE
    - NDA_DST
    - RTA_DST, RTA_SRC, RTA_GATEWAY, RTA_PREFSRC
    - FRA_SRC, FRA_DST
  - ipv4
    - IFA_BROADCAST
    - IFLA_GENEVE_REMOTE
    - IFLA_IPTUN_6RD_RELAY_PREFIX

Reviewed-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://patch.msgid.link/20251117024457.3034-3-liuhangbin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>