perf trace: Beautify renameat2's flags argument

  # strace -e renameat2 -f perf trace -e rename* mv c /tmp
  strace: Process 10824 attached
  [pid 10824] renameat2(AT_FDCWD, "c", AT_FDCWD, "/tmp", RENAME_NOREPLACE) = -1 EXDEV (Invalid cross-device link)
  [pid 10824] renameat2(AT_FDCWD, "c", AT_FDCWD, "/tmp/c", RENAME_NOREPLACE) = -1 EEXIST (File exists)
       1.857 ( 0.008 ms): mv/10824 renameat2(olddfd: CWD, oldname: 0x7ffc72ff3d81, newdfd: CWD, newname: 0x7ffc72ff3d83, flags: NOREPLACE) = -1 EXDEV Invalid cross-device link
       2.002 ( 0.006 ms): mv/10824 renameat2(olddfd: CWD, oldname: 0x7ffc72ff3d81, newdfd: CWD, newname: 0x55ad609efcc0, flags: NOREPLACE) = -1 EEXIST File exists
  mv: 'c' and '/tmp/c' are the same file
  [pid 10824] +++ exited with 1 +++
  --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=10824, si_uid=0, si_status=1, si_utime=0, si_stime=0} ---
  +++ exited with 0 +++
  #

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-glyt6nzlt1yx56m5bshy6g83@git.kernel.org


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