ice: fix FDir IPv6 flexbyte

The packet classifier would occasionally misrecognize an IPv6 training
packet when the next protocol field was 0. The correct value for
unspecified protocol is IPPROTO_NONE.

Fixes: 165d80d6 ("ice: Support IPv6 Flow Director filters")
Signed-off-by: Henry Tieman <henry.w.tieman@intel.com>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/ice/ice_ethtool_fdir.c

@@ -1576,7 +1576,13 @@ ice_set_fdir_input_set(struct ice_vsi *vsi, struct ethtool_rx_flow_spec *fsp,
 		       sizeof(struct in6_addr));
 		input->ip.v6.l4_header = fsp->h_u.usr_ip6_spec.l4_4_bytes;
 		input->ip.v6.tc = fsp->h_u.usr_ip6_spec.tclass;
+
+		/* if no protocol requested, use IPPROTO_NONE */
+		if (!fsp->m_u.usr_ip6_spec.l4_proto)
+			input->ip.v6.proto = IPPROTO_NONE;
+		else
 			input->ip.v6.proto = fsp->h_u.usr_ip6_spec.l4_proto;
+
 		memcpy(input->mask.v6.dst_ip, fsp->m_u.usr_ip6_spec.ip6dst,
 		       sizeof(struct in6_addr));
 		memcpy(input->mask.v6.src_ip, fsp->m_u.usr_ip6_spec.ip6src,