net: mvpp2: parser fix PPPoE

net: mvpp2: parser fix PPPoE

[ Upstream commit 031a416c2170866be5132ae42e14453d669b0cb1 ]

In PPPoE add all IPv4 header option length to the parser
and adjust the L3 and L4 offset accordingly.
Currently the L4 match does not work with PPPoE and
all packets are matched as L3 IP4 OPT.

Fixes: 3f518509dedc ("ethernet: Add new driver for Marvell Armada 375 network unit")
Signed-off-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>