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