perf trace: Allow configuring if the syscall start timestamp should be printed
# trace -e open*,close,*sleep sleep 1
0.000 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC ) = 3
0.016 close(fd: 3 ) = 0
0.024 openat(dfd: CWD, filename: /lib64/libc.so.6, flags: CLOEXEC ) = 3
0.074 close(fd: 3 ) = 0
0.235 openat(dfd: CWD, filename: /usr/lib/locale/locale-archive, flags: CLOEXEC) = 3
0.251 close(fd: 3 ) = 0
0.285 nanosleep(rqtp: 0x7ffd68e6d620, rmtp: 0 ) = 0
1000.386 close(fd: 1 ) = 0
1000.395 close(fd: 2 ) = 0
#
# perf config trace.show_timestamp=no
# trace -e open*,close,*sleep sleep 1
openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC ) = 3
close(fd: 3 ) = 0
openat(dfd: CWD, filename: /lib64/libc.so.6, flags: CLOEXEC ) = 3
close(fd: 3 ) = 0
openat(dfd: CWD, filename: , flags: CLOEXEC ) = 3
close(fd: 3 ) = 0
nanosleep(rqtp: 0x7fffa79c38e0, rmtp: 0 ) = 0
close(fd: 1 ) = 0
close(fd: 2 ) = 0
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-mjjnicy48367jah6ls4k0nk8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>