use correct hz for rto,ato

The function get_hz() returns the psched hz value which is wrong
for anything other than tc usage. Should be user hz instead, but
kernel is broken (patch sent) and this code doesn't get hit on
current systems (netlink is used first).

misc/ss.c

@@ -1191,10 +1191,11 @@ static int tcp_show_line(char *line, const struct filter *f, int family)
 		}
 	}
 	if (show_tcpinfo) {
-		if (s.rto && s.rto != 3*get_hz())
-			printf(" rto:%g", (double)s.rto/get_hz());
+		int hz = get_user_hz();
+		if (s.rto && s.rto != 3*hz)
+			printf(" rto:%g", (double)s.rto/hz);
 		if (s.ato)
-			printf(" ato:%g", (double)s.ato/get_hz());
+			printf(" ato:%g", (double)s.ato/hz);
 		if (s.cwnd != 2)
 			printf(" cwnd:%d", s.cwnd);
 		if (s.ssthresh != -1)