perf ui browser hists: Set actions->thread before calling do_zoom_thread()

perf ui browser hists: Set actions->thread before calling do_zoom_thread()

In 7cecb7fe8388d5c3 ("perf hists: Move sort__has_comm into struct
perf_hpp_list") it assumes that act->thread is set prior to calling
do_zoom_thread().

This doesn't happen when we use ESC or the Left arrow key to Zoom out of
a specific thread, making this operation not to work and we get stuck
into the thread zoom.

In 6422184b087ff435 ("perf hists browser: Simplify zooming code using
pstack_peek()") it says no need to set actions->thread, and at that
point that was true, but in 7cecb7fe8388d5c3 a actions->thread == NULL
check was added before the zoom out of thread could kick in.

We can zoom out using the alternative 't' thread zoom toggle hotkey to
finally set actions->thread before calling do_zoom_thread() and zoom
out, but lets also fix the ESC/Zoom out of thread case.

Fixes: 7cecb7fe8388d5c3 ("perf hists: Move sort__has_comm into struct perf_hpp_list")
Reported-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/Z_TYux5fUg2pW-pF@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>