perf tools: Use zfree to help detect use after free bugs

Several areas already used this technique, so do some audit to
consistently use it elsewhere.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-9sbere0kkplwe45ak6rk4a1f@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --cc tools/perf/builtin-diff.c
Simple merge

diff --cc tools/perf/builtin-sched.c
Simple merge

diff --cc tools/perf/builtin-script.c
Simple merge

diff --cc tools/perf/ui/browsers/hists.c
Simple merge

diff --cc tools/perf/ui/stdio/hist.c
Simple merge

diff --cc tools/perf/util/annotate.c
Simple merge

diff --cc tools/perf/util/cgroup.c
Simple merge

diff --cc tools/perf/util/comm.c
Simple merge

diff --cc tools/perf/util/evsel.c
Simple merge

diff --cc tools/perf/util/header.c
Simple merge

diff --cc tools/perf/util/help.c
Simple merge

diff --cc tools/perf/util/hist.c
Simple merge

diff --cc tools/perf/util/parse-events.c
Simple merge

diff --cc tools/perf/util/pmu.c
Simple merge

diff --cc tools/perf/util/probe-event.c
Simple merge

diff --cc tools/perf/util/probe-finder.c
Simple merge

diff --cc tools/perf/util/session.c
Simple merge

diff --cc tools/perf/util/srcline.c
Simple merge

diff --cc tools/perf/util/strbuf.c
Simple merge

diff --cc tools/perf/util/strfilter.c
Simple merge

diff --cc tools/perf/util/string.c
Simple merge

diff --cc tools/perf/util/strlist.c
Simple merge

diff --cc tools/perf/util/svghelper.c
Simple merge

diff --cc tools/perf/util/symbol-elf.c
Simple merge

diff --cc tools/perf/util/symbol-minimal.c
Simple merge

diff --cc tools/perf/util/symbol.c
Simple merge

diff --cc tools/perf/util/thread_map.c
Simple merge

diff --cc tools/perf/util/trace-event-info.c
Simple merge

diff --cc tools/perf/util/values.c
Simple merge