perf record: Set timestamp boundary for AUX area events

AUX area data is not processed by 'perf record' and consequently the
 --timestamp-boundary option may result in no values for "time of first
sample" and "time of last sample". However there are non-sample events
that can be used instead, namely 'itrace_start' and 'aux'.
'itrace_start' is issued before tracing starts, and 'aux' is issued
every time data is ready.

Implement tool callbacks for those two for 'perf record', to update the
timestamp boundary.

Example:

 $ perf record -e intel_pt//u --timestamp-boundary uname
 Linux
 [ perf record: Woken up 1 times to write data ]
 [ perf record: Captured and wrote 0.022 MB perf.data ]
 $ perf script --header-only | grep "time of"
 # time of first sample : 4574.835541
 # time of last sample : 4574.835907
 $ perf script --itrace=be -F-ip | head -1
           uname 13752 [001]  4574.835589:          1 branches:uH:
 $ perf script --itrace=be -F-ip | tail -1
           uname 13752 [001]  4574.835867:          1 branches:uH:
 $

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20210503064222.5319-1-adrian.hunter@intel.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>