selftests/bpf: Return true/false (not 1/0) from bool functions

Return boolean values ("true" or "false") instead of 1 or 0 from bool
functions. This fixes the following warnings from coccicheck:

./tools/testing/selftests/bpf/progs/test_xdp_noinline.c:567:9-10: WARNING:
return of 0/1 in function 'get_packet_dst' with return type bool
./tools/testing/selftests/bpf/progs/test_l4lb_noinline.c:221:9-10: WARNING:
return of 0/1 in function 'get_packet_dst' with return type bool

Signed-off-by: Haowen Bai <[e-mail]>
Signed-off-by: Andrii Nakryiko <[e-mail]>
Reviewed-by: Shuah Khan <[e-mail]>
Acked-by: Yonghong Song <[e-mail]>
Link: https://lore.kernel.org/bpf/[e-mail]

tools/testing/selftests/bpf/progs/test_l4lb_noinline.c

···
 
 	if (hash != 0x358459b7 /* jhash of ipv4 packet */  &&
 	    hash != 0x2f4bc6bb /* jhash of ipv6 packet */)
-		return 0;
+		return false;
 
 	real_pos = bpf_map_lookup_elem(&ch_rings, &key);
 	if (!real_pos)

tools/testing/selftests/bpf/progs/test_xdp_noinline.c

···
 	hash = get_packet_hash(pckt, hash_16bytes);
 	if (hash != 0x358459b7 /* jhash of ipv4 packet */  &&
 	    hash != 0x2f4bc6bb /* jhash of ipv6 packet */)
-		return 0;
+		return false;
 	key = 2 * vip_info->vip_num + hash % 2;
 	real_pos = bpf_map_lookup_elem(&ch_rings, &key);
 	if (!real_pos)
-		return 0;
+		return false;
 	key = *real_pos;
 	*real = bpf_map_lookup_elem(&reals, &key);
 	if (!(*real))
-		return 0;
+		return false;
 	if (!(vip_info->flags & (1 << 1))) {
 		__u32 conn_rate_key = 512 + 2;
 		struct lb_stats *conn_rate_stats =
 		    bpf_map_lookup_elem(&stats, &conn_rate_key);
 
 		if (!conn_rate_stats)
-			return 1;
+			return true;
 		cur_time = bpf_ktime_get_ns();
 		if ((cur_time - conn_rate_stats->v2) >> 32 > 0xffFFFF) {
 			conn_rate_stats->v1 = 1;
···
 		} else {
 			conn_rate_stats->v1 += 1;
 			if (conn_rate_stats->v1 >= 1)
-				return 1;
+				return true;
 		}
 		if (pckt->flow.proto == IPPROTO_UDP)
 			new_dst_lru.atime = cur_time;
 		new_dst_lru.pos = key;
 		bpf_map_update_elem(lru_map, &pckt->flow, &new_dst_lru, 0);
 	}
-	return 1;
+	return true;
 }
 
 __attribute__ ((noinline))