tools: bpftool: don't use hex numbers in JSON output

JSON does not accept hex numbers with 0x prefix.  Simply print
as decimal numbers, JSON should be primarily machine-readable.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Fixes: 831a0aaf ("tools: bpftool: add JSON output for `bpftool map *` commands")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

tools/bpf/bpftool/map.c

@@ -428,7 +428,7 @@ static int show_map_close_json(int fd, struct bpf_map_info *info)
 		jsonw_string_field(json_wtr, "name", info->name);
 
 	jsonw_name(json_wtr, "flags");
-	jsonw_printf(json_wtr, "%#x", info->map_flags);
+	jsonw_printf(json_wtr, "%d", info->map_flags);
 
 	print_dev_json(info->ifindex, info->netns_dev, info->netns_ino);