netlink: specs: tc: remove duplicate nests

netlink: specs: tc: remove duplicate nests

tc-act-stats-attrs and tca-stats-attrs are almost identical.
The only difference is that the latter has sub-message decoding
for app, rather than declaring it as a binary attr.

tc-act-police-attrs and tc-police-attrs are identical but for
the TODO annotations.

Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250520161916.413298-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>