examples/l3fwd: fix IPv6 packet type parse
examples/l3fwd: fix IPv6 packet type parse

Fix a typo that cause IPv6 packet type not be parsed.

Fixes: 71a7e2424e07 ("examples/l3fwd: fix using packet type blindly")
Cc: stable@dpdk.org

Signed-off-by: Qi Zhang <9e9e58ffa71a29bb7b87766b362515be648fcbe0@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk