In IPv6, the broadcast MAC address is not used. Instead, it should use
the multicast address (see RFC RFC2464).
Add IPV6_ALL_NODE_ETH_ADDR macro for clarity.
Signed-off-by: Sean Edmond <seanedmond@microsoft.com>
Reviewed-by: Jerome Forissier <jerome.forissier@linaro.org>
(cherry picked from commit 9a6964e419)