htb: rename b4 buffer to b3 to make its name more consistent

b3 buffer has been deleted previously so b2 is followed by b4
which is not consistent.
Signed-off-by: Dmitrii Shcherbakov <fw.dmitrii@yandex.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Phil Sutter <phil@nwl.cc>

tc/q_htb.c

@@ -273,7 +273,7 @@ static int htb_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 	__u64 rate64, ceil64;
 	SPRINT_BUF(b1);
 	SPRINT_BUF(b2);
-	SPRINT_BUF(b4);
+	SPRINT_BUF(b3);
 
 	if (opt == NULL)
 		return 0;
@@ -310,7 +310,7 @@ static int htb_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 		cbuffer = tc_calc_xmitsize(ceil64, hopt->cbuffer);
 		linklayer = (hopt->rate.linklayer & TC_LINKLAYER_MASK);
 		if (linklayer > TC_LINKLAYER_ETHERNET || show_details)
-			fprintf(f, "linklayer %s ", sprint_linklayer(linklayer, b4));
+			fprintf(f, "linklayer %s ", sprint_linklayer(linklayer, b3));
 		if (show_details) {
 			fprintf(f, "burst %s/%u mpu %s ",
 				sprint_size(buffer, b1),