tools lib: Adopt zalloc()/zfree() from tools/perf

Eroding a bit more the tools/perf/util/util.h hodpodge header.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-natazosyn9rwjka25tvcnyi0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-bench.c

@@ -17,7 +17,6 @@
  *  epoll ... Event poll performance
  */
 #include "perf.h"
-#include "util/util.h"
 #include <subcmd/parse-options.h>
 #include "builtin.h"
 #include "bench/bench.h"
@@ -26,6 +25,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/prctl.h>
+#include <linux/zalloc.h>
 
 typedef int (*bench_fn_t)(int argc, const char **argv);