[qca-nss-sfe] PPPoE offload fixes

1. Fix protocol and endianess
2. Fix copyright year style
3. Pass non-NULL l2_info and check parse flags before using l2_info

Change-Id: I7801834b224a39a04450fdacbbb9cb9620b4221c
Signed-off-by: Guduri Prathyusha <quic_gprathyu@quicinc.com>
diff --git a/sfe_ipv4.h b/sfe_ipv4.h
index e614cbc..9f2e1f4 100644
--- a/sfe_ipv4.h
+++ b/sfe_ipv4.h
@@ -3,7 +3,7 @@
  *	Shortcut forwarding engine header file for IPv4.
  *
  * Copyright (c) 2013-2016, 2019-2020, The Linux Foundation. All rights reserved.
- * Copyright (c) 2021,2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2021-2022 Qualcomm Innovation Center, Inc. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -237,7 +237,7 @@
 	SFE_IPV4_EXCEPTION_EVENT_DATAGRAM_INCOMPLETE,
 	SFE_IPV4_EXCEPTION_EVENT_IP_OPTIONS_INCOMPLETE,
 	SFE_IPV4_EXCEPTION_EVENT_UNHANDLED_PROTOCOL,
-	SFE_IPV4_EXCEPTION_EVENT_PPPOE_HEADER_ENCAP_FAILED,
+	SFE_IPV4_EXCEPTION_EVENT_NO_HEADROOM,
 	SFE_IPV4_EXCEPTION_EVENT_INVALID_PPPOE_SESSION,
 	SFE_IPV4_EXCEPTION_EVENT_INCORRECT_PPPOE_PARSING,
 	SFE_IPV4_EXCEPTION_EVENT_PPPOE_NOT_SET_IN_CME,