net/sched: fix incorrect vlan_push_eth dest field

Seems like a potential copy-paste bug slipped in here,
the second memcpy should of course be populating src
and not dest.

Fixes: ab95465c

 ("net/sched: add vlan push_eth and pop_eth action to the hardware IR")
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Link: https://lore.kernel.org/r/20220323092506.21639-1-louis.peens@corigine.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>