clatd: use struct instead of direct u8[] for buffer

(this will allow adding more headers)

Note the ethernet header may or may not be present,
so it has to stay as part of the payload.

Test: TreeHugger
Bug: 265591307
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I4e64fd1d15ac26ebb7a41ee9884b506625018fda
1 file changed