bpftool: Fix typo in error message

s/at at/at a/
Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240411164258.533063-3-thorsten.blum@toblux.com

tools/bpf/bpftool/prog.c

@@ -2081,7 +2081,7 @@ static int profile_parse_metrics(int argc, char **argv)
 		NEXT_ARG();
 	}
 	if (selected_cnt > MAX_NUM_PROFILE_METRICS) {
-		p_err("too many (%d) metrics, please specify no more than %d metrics at at time",
+		p_err("too many (%d) metrics, please specify no more than %d metrics at a time",
 		      selected_cnt, MAX_NUM_PROFILE_METRICS);
 		return -1;
 	}