netlink: specs: wireless: add a spec for nl80211

Add a rudimentary YNL spec for nl80211 that covers get-wiphy,
get-interface and get-protocol-features.

./tools/net/ynl/pyynl/cli.py --family nl80211 \
    --do get-protocol-features
{'protocol-features': {'split-wiphy-dump'}}

./tools/net/ynl/pyynl/cli.py --family nl80211 \
    --dump get-wiphy --json '{ "split-wiphy-dump": true }'

./tools/net/ynl/pyynl/cli.py --family nl80211 \
    --dump get-interface

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Link: https://patch.msgid.link/20250211120127.84858-11-donald.hunter@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>