Always set the IP version in the TCP input path, to preserve

the header field for possible later IPSEC SPD lookup, even
when the kernel is built without 'options INET6'.

PR:		kern/57760
MFC after:	1 week
Submitted by:	Joachim Schueth

sys/netinet/tcp_input.c

@@ -548,10 +548,8 @@ tcp_input(m, off0)
 			tcpstat.tcps_rcvbadsum++;
 			goto drop;
 		}
-#ifdef INET6
 		/* Re-initialization for later version check */
 		ip->ip_v = IPVERSION;
-#endif
 	}
 
 	/*

sys/netinet/tcp_reass.c

@@ -548,10 +548,8 @@ tcp_input(m, off0)
 			tcpstat.tcps_rcvbadsum++;
 			goto drop;
 		}
-#ifdef INET6
 		/* Re-initialization for later version check */
 		ip->ip_v = IPVERSION;
-#endif
 	}
 
 	/*