bpftool: Fix print error when show bpf map

If there is no btf_id or frozen, it will not show the pids, but the pids don't
depend on any one of them.

Below is the result after this change:

  $ ./bpftool map show
  2: lpm_trie  flags 0x1
	key 8B  value 8B  max_entries 1  memlock 4096B
	pids systemd(1)
  3: lpm_trie  flags 0x1
	key 20B  value 8B  max_entries 1  memlock 4096B
	pids systemd(1)

While before this change, the 'pids systemd(1)' can't be displayed.

Fixes: 9330986c ("bpf: Add bloom filter map implementation")
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220320060815.7716-1-laoar.shao@gmail.com

tools/bpf/bpftool/map.c

@@ -620,17 +620,14 @@ static int show_map_close_plain(int fd, struct bpf_map_info *info)
 					    u32_as_hash_field(info->id))
 			printf("\n\tpinned %s", (char *)entry->value);
 	}
-	printf("\n");
 
 	if (frozen_str) {
 		frozen = atoi(frozen_str);
 		free(frozen_str);
 	}
 
-	if (!info->btf_id && !frozen)
-		return 0;
-
-	printf("\t");
+	if (info->btf_id || frozen)
+		printf("\n\t");
 
 	if (info->btf_id)
 		printf("btf_id %d", info->btf_id);