tools: bpftool: use more common tag format

Program tag is usually displayed as string of bytes without
any separators (e.g. as "aa5520b1090cfeb6" vs MAC addr-like
format bpftool uses currently: "aa:55:20:b1:09:0c:fe:b6").
Make bptfool use the more common format both for displaying
the tag and selecting the program by tag.

This was pointed out in review but I misunderstood the comment.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/bpf/bpftool/Documentation/bpftool-prog.rst

@@ -55,7 +55,7 @@ EXAMPLES
 **# bpftool prog show**
 ::
 
-  10: xdp  name some_prog  tag 00:5a:3d:21:23:62:0c:8b
+  10: xdp  name some_prog  tag 005a3d2123620c8b
 	loaded_at Sep 29/20:11  uid 0
 	xlated 528B  jited 370B  memlock 4096B  map_ids 10
 

tools/bpf/bpftool/main.h

@@ -53,8 +53,7 @@
 #define NEXT_ARGP()	({ (*argc)--; (*argv)++; if (*argc < 0) usage(); })
 #define BAD_ARG()	({ err("what is '%s'?\n", *argv); -1; })
 
-#define BPF_TAG_FMT	"%02hhx:%02hhx:%02hhx:%02hhx:"	\
-			"%02hhx:%02hhx:%02hhx:%02hhx"
+#define BPF_TAG_FMT	"%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx"
 
 #define HELP_SPEC_PROGRAM						\
 	"PROG := { id PROG_ID | pinned FILE | tag PROG_TAG }"

tools/bpf/bpftool/prog.c

@@ -224,7 +224,7 @@ static int show_prog(int fd)
 		printf("name %s  ", info.name);
 
 	printf("tag ");
-	print_hex(info.tag, BPF_TAG_SIZE, ":");
+	print_hex(info.tag, BPF_TAG_SIZE, "");
 	printf("\n");
 
 	if (info.load_time) {