Remove "#ifdef INET6" block from in_setpeeraddr()

[Vitaliy Makkoveev]

We always call in6_setpeeraddr() and never call in_setpeeraddr() fro the
inet6 case.

Index: sys/netinet/in_pcb.c
===================================================================
RCS file: /cvs/src/sys/netinet/in_pcb.c,v
retrieving revision 1.273
diff -u -p -r1.273 in_pcb.c
--- sys/netinet/in_pcb.c        30 Aug 2022 11:53:04 -0000      1.273
+++ sys/netinet/in_pcb.c        2 Sep 2022 14:59:02 -0000
@@ -649,13 +649,6 @@ in_setpeeraddr(struct inpcb *inp, struct
 {
        struct sockaddr_in *sin;
 
-#ifdef INET6
-       if (sotopf(inp->inp_socket) == PF_INET6) {
-               in6_setpeeraddr(inp, nam);
-               return;
-       }
-#endif /* INET6 */
-
        nam->m_len = sizeof(*sin);
        sin = mtod(nam, struct sockaddr_in *);
        memset(sin, 0, sizeof(*sin));