bpftool: Silence build warning about calloc()

There exists the following warning when building bpftool:

  CC      prog.o
prog.c: In function ‘profile_open_perf_events’:
prog.c:2301:24: warning: ‘calloc’ sizes specified with ‘sizeof’ in the earlier argument and not in the later argument [-Wcalloc-transposed-args]
 2301 |                 sizeof(int), obj->rodata->num_cpu * obj->rodata->num_metric);
      |                        ^~~
prog.c:2301:24: note: earlier argument should specify number of elements, later size of each element

Tested with the latest upstream GCC which contains a new warning option
-Wcalloc-transposed-args. The first argument to calloc is documented to
be number of elements in array, while the second argument is size of each
element, just switch the first and second arguments of calloc() to silence
the build warning, compile tested only.

Fixes: 47c09d6a9f67 ("bpftool: Introduce "prog profile" command")
Signed-off-by: Tiezhu Yang <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Reviewed-by: Quentin Monnet <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

Author: seehearfeel

src/prog.c

@@ -2298,7 +2298,7 @@ static int profile_open_perf_events(struct profiler_bpf *obj)
 	int map_fd;
 
 	profile_perf_events = calloc(
-		sizeof(int), obj->rodata->num_cpu * obj->rodata->num_metric);
+		obj->rodata->num_cpu * obj->rodata->num_metric, sizeof(int));
 	if (!profile_perf_events) {
 		p_err("failed to allocate memory for perf_event array: %s",
 		      strerror(errno));