perf trace beauty: Beautify renameat2's fd arg wrt AT_FDCWD

perf trace beauty: Beautify renameat2's fd arg wrt AT_FDCWD

Just like is done with the 'renameat' syscall.

  # strace -e renameat2 -f perf trace -e rename* mv c /tmp
  [pid 12334] renameat2(AT_FDCWD, "c", AT_FDCWD, "/tmp", RENAME_NOREPLACE) = -1 EXDEV (Invalid cross-device link)
  [pid 12334] renameat2(AT_FDCWD, "c", AT_FDCWD, "/tmp/c", RENAME_NOREPLACE) = -1 EEXIST (File exists)
     1.947 ( 0.007 ms): mv/12334 renameat2(olddfd: CWD, oldname: 0x7ffce8b7fd81, newdfd: CWD, newname: 0x7ffce8b7fd83, flags: 1) = -1 EXDEV Invalid cross-device link
     2.073 ( 0.009 ms): mv/12334 renameat2(olddfd: CWD, oldname: 0x7ffce8b7fd81, newdfd: CWD, newname: 0x55ce7f0a1cc0, flags: 1mv: ) = -1 EEXIST File exists'c' and '/tmp/c' are the same file
  #

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-8q9l92eh9eee3y2bwyqku3tc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>