Remove unused mtag variable.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
Remove code related to PACKET_TAG_IPSEC_IN_CRYPTO_DONE mbuf tag.
It isn't used in FreeBSD.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
Remove now unused mtag argument from ipsec*_common_input_cb.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
Remove flags and tunalready arguments from ipsec4_process_packet()
and make its prototype similar to ipsec6_process_packet.
The flags argument isn't used here, tunalready is always zero.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
handle "Kana" and "Eisu" keys on Apple Wireless Keyboard (JIS)

PR:		187470
Submitted by:	naito.yuichiro
MFC after:	1 week
Remove flag/flags argument from the following functions:
 ipsec_getpolicybyaddr()
 ipsec4_checkpolicy()
 ip_ipsec_output()
 ip6_ipsec_output()

The only flag used here was IP_FORWARDING.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
Initialize error variable.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
Treat errors when retrieving security policy as policy violation.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
Use ipsec4_in_reject() to simplify ip_ipsec_fwd() and ip_ipsec_input().
ipsec4_in_reject() does the same things, also it counts policy violation
errors.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
Add myself.
Use ipsec6_in_reject() to simplify ip6_ipsec_fwd() and ip6_ipsec_input().
ipsec6_in_reject() does the same things, also it counts policy violation
errors.

Do IPSEC check in the ip6_forward() after addresses checks.
Also use ip6_ipsec_fwd() to make code similar to IPv4 implementation.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC
Do not count security policy violation twice.
ipsec*_in_reject() do this by their own.

Obtained from:	Yandex LLC
Sponsored by:	Yandex LLC